4. Take Your Memory Stick And

Sony has deigned to open its console to the outside world... slightly. On the side, under a little trapdoor, is a Memory Stick Duo reader for feeding content to the console. But then Sony immediately slams the door, by insisting on inventing new proprietary formats. These new Memory Sticks are even incompatible with other ones - the PSP accepts only the Duo version!

It's true that prices have come down, but they're still much more expensive than other memory cards. If you want a little space, you'll need 1 GB, but it's still hard to find them at a reasonable price. 512 MB cost around $70, while SD costs $40. Consumers might be willing to accept the extra cost, but if they already have a camera, PDA, or other device that uses SD, they'll be forced to invest in a Stick for a single purpose.

Finally, and worst of all, the Memory Stick Duo format is never built into PCs, and readers are rare and expensive.