Motorola MPX220..
hated it at first; now, i love it. It's my PDA, mp3-player, and general entertainment device. I can synchronize with Outlook, play downloaded games (even while listening to mp3s), browse the Internet (the actual internet.. not some shtty cell-phone network), read email..
I even have an NES emulator for my mpx220. It plays NES games.. with sound, full-speed..
ya.. there's been problems at first, but it originally shipped with version .33 firmware.. Now, you can download 1.49 firmware for it.