If the Zune can wirelessly sync over your home network, why can't your iPhone? A developer's made an automatic GUI syncing tool that essentially rsync's a folder on your computer to a folder on your iPhone/iTouch. That by itself is pretty lame and quite limited—especially compared with a full sync you get when you…
Here's a plugin for iSync that lets you sync your calendar, to-do and address book entries with your Sony Ericsson K800i. Normally your iSync would just give you a 'wtfomglolzers' when you tried to sync, but this plugin should teach it a thing or two.
The Missing Sync is a piece of software for OS X to let you sync your PIM information with your mobile device, like a phone or a PDA, that's not supported natively with OS X. If you have a WM5 device, go grab the Missing Sync 2.5 beta and sync up your Pocket PC.