iSwitcher is a theme / keyboad swapping iPhone application. iSwitcher is 100% compatible with SummerBoard (verified with all versions up to 2.1).

What’s new?

Faster and more useful iSwitcher can now install icons with spaces in their name. I realize this doesn’t sound like a big deal. Trust me, it is. 😀 Version 1.56 is also about 15% faster than v1.45 when loading icon themes and about 20% faster when loading keyboards. (nice…)

Custom Icons We can now load custom icons for each theme. Say you are using the 1984 theme and the next, “can’t do without it” iPhone app is released and you don’t have an icon to match. If the theme developer, or anyone creates a matching icon, all you have to do is put it into the “Icons” subfolder and when iSwitcher is loading that theme, it will install your new icon. This also applies to your own custom apps. I use four one button “dialer” apps and I have made custom icons for all the matching themes.

http://code.google.com/p/iswitcher/