Dockable Cases

The Contour Flick.

It will fit in any dock that is made for the 3G since it has a flap that exposes the bottom when you need to dock. It's made from hard plastic so there is potential for the flap to scratch the sides with too much use...I haven't noticed any yet though.

 

Sena has a dockable case. http://www.senacases.com/Brands/iPhone-3G-Cases/SENA-DOCKABLE-CASE-FOR-iPHONE-3G....I like it besides the flap with button/snap to hold the lid closed

Vaja has a dockable case for the original iPhone. see www.vajacases.com....I'd like to buy one of these if they come out for the 3G...have to expect theyre coming soon... Only objections to the first edition was the magnet holding the lid closed (little paranoid) and the fact that the home button is covered...I'd prefer to press the button directly. And obviously the price is a concern, but sounds like you get what you pay for with Vaja at least

There is also the Griffin one, which looks pretty good. http://www.griffintechnology.com/products/elanform3g