If going all-out with a custom Colorware paint job for your iPhone is a bit too over-the-top, perhaps some new iPhone skin kits from the everlasting DecalGirl are more your style. Printed on premium grade adhesive-backed cast vinyl with a high-gloss clear protective coating, all of their skins boast easy repositioning and goo-free removal (I've never used one of these - can anyone comment on their experiences with accessories like this and their goo factor?).
For the iPhone, DecalGirl already has over 160 designs that can easily be sorted by a large selection of colors and themes, and as a bonus, you also receive a matching iPhone wallpaper to complete the redecoration. Skins seem to all be priced at a reasonable $6.99, with extra protective or stylistic finishes - like Screen Armor, Matte and Gloss - available for $4.50 to $9.99.