The flash-based MP3 player market has gotten fairly complex, thanks to an ever-changing cast of characters and an explosion of new features. But there's a path through the maze, and it begins with understanding what you need, want, and are willing to spend.

For starters: You need something that works with your computer. If you have a Microsoft Windows-based PC, all players are compatible. If you have a Mac, you've got two options: an Apple iPod or a device that's USB Mass Storage Class-compliant (USB MC), meaning that it can be plugged into a computer without software installation and be managed via drag-and-drop. Many popular players, and some USB MC players, work only with Windows Media Player (WMP) on machines running Windows.

You should also consider how tech-savvy you are. There are no-fuss, no-muss players that you simply plug into your computer and drag music onto. Then there are players that require a little bit of fiddling around with software like iTunes or WMP—and in some cases, with additional proprietary software. USB MC players are best for nontechies who don't have huge music collections. Of course, iPods are also very easy to use, thanks to their excellent integration with iTunes. Devices that work only with WMP tend to be somewhat more challenging to manage because the hardware/software integration isn't as polished.

If you plan on using online download or subscription services like Napster and Yahoo! Music Unlimited, you need a player that is compatible with Microsoft's PlaysForSure (aka Windows Media DRM 10). Note, too, that tracks purchased from Apple's iTunes Music Store will work only on iPods.

Flash players' capacity currently tops out at 4GB, with the lone exception of SanDisk's 6GB player. Unless you use your MP3 player only at, say, the gym, you'll probably want at least 1GB of storage space. The general belief is that you can fit 250 songs per ­gigabyte, but this depends entirely on the quality and format of your music files. In real-world usage, you can expect from 130 to 150 songs per gigabyte.

Aside from music playback, the three most important extra features for many users are photo/video playback, recording, and FM radio. Handy features like photo playback, FM radio, and voice recording are quickly becoming standard on MP3 players, as are less useful features such as line-in recording. If you like to watch movie trailers or other short video clips, there are a host of video-capable flash players, though none of them have impressed me with the quality and smoothness of video.

Of course, the most important consideration for many is price. At $100 or less, you've got plenty of options; you can expect few extras and a capacity of 1GB or less. For around $150, you can get a player with lots of extra features, and at $200 you start moving into the higher capacities like 2GB and up. The highest-capacity flash-based players cost $250 to $299, and I'm not expecting those prices to drop very much before the end of this year.

What are my choices?
Every month, manufacturers unleash even more MP3 players to an increasingly confused public. Not only do these devices have wildly divergent features, but ongoing format wars mean the MP3 player you choose dictates where you can buy your digital music. These devices are anything but one-size-fits-all.

First, there's the question of design. A player can have every feature in the world, but if the design doesn't match your lifestyle or if the interface is impenetrable, you still won't enjoy it. You'll want to look closely at performance; sound quality and battery life can make or break a player, especially if you travel a lot or have the so-called golden ears of an audiophile.

Before you start checking out specific models, you should have a basic understanding of the types of MP3 players available. Note: All types of player mentioned below can play other formats besides MP3, such as WMA, ATRAC3, OGG, or AAC, but we still refer to them as MP3 players.

Types of players:
Hard drive based
Micro hard drive based
Flash based
MP3 CD

Hard drive-based players

Most likely, a high-capacity player can accommodate every song you've ever purchased. Hard drives run from 10GB on up, and large players such as the 60GB Apple iPod can hold around 17,000 songs, assuming an average file size of 3.5MB per tune.

Pros: They store all your music on one device. They also tend to have more features and larger screens and are overall easier to use.
Cons: These players are usually built around a 1.8-inch hard drive; thus, they are larger and heavier than the others. Also, hard drives have moving parts, so these players aren't ideal for strenuous physical activity. Finally, most use rechargeable batteries (usually lasting 8 to 20 hours per charge) that you can't replace yourself, so after several years, you might have to pay for a new model or pay to get the battery replaced.

Micro hard drive-based players

Straddling the line between full-size hard drive-based MP3 players and compact, flash-based players, these models aim to give you the best of both worlds by using miniature hard drives (about 1 inch or less in diameter) with capacities of up to 8GB. Players such as the Creative Zen Micro Photo can't store as much music as a 30GB Cowon iAudio X5L, but they feel a lot lighter in the pocket.

Pros: They're smaller and lighter than high-capacity players but still hold more tunes than flash-based models with the same price.
Cons: You get fewer megabytes per dollar than you do with a larger player, and these models have many of the same disadvantages of larger hard drive-based units, including the moving parts that limit physical activity and nonremovable batteries that eventually wear out and need to be replaced. Luckily, many new micro drive-based players such as the Creative Zen Micro feature a user-replaceable battery.

Flash-based players

The original MP3 player design, these have no moving parts and are known for their shockproof operation and ultracompact dimensions. Devices range in capacity from 32MB to 6GB, though most new players don't go below 512MB. SanDisk's MP3 line, for example, includes exclusively flash-based players.

Pros: Flash-based players are tiny. They also have no moving parts, so their batteries last longer, and you can jog, snowboard, or bungee jump with them without causing skipping or damage. Many flash players include lots of extra features such as voice and line-in recording.
Cons: The aforementioned extras can make flash players a bit harder to use, and they have the highest per-megabyte cost and max out at 6GB.

MP3 CD players

These look just like portable CD players, except they can read data CDs filled with digital music. You can burn approximately 150 MP3 songs (10 albums) on one 650MB disc. But if you want to take your CD collection with you, no worries--these devices can play standard CDs, as well.

Pros: These are the least expensive of all types of MP3 players, and they use incredibly cheap replaceable media (CD-R/RW discs).
Cons: They're large and can skip when jostled.

for my personal choice it is the MP3 CD plpayers... easiest to use and the cheapest... it works for me...

Ohhhh I'm sure the RIAA will try to find a way to put a stop in this too!

iPod + Rockbox =