Tech Guide: MP3 player buying guide

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 Creative Nomad Jukebox Zen Xtra 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.

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 6 to 16 hours per charge) that you can't replace yourself, so after a couple of years, you might have to pay for a new model.

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 in diameter) with capacities of up to 5GB. Players such as the Rio Nitrus can't store as much music, 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.

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 1GB. Creative's Nomad MuVo line, for example, includes mostly 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.

Cons: They have the highest per-megabyte cost and max out at 1GB.

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.