For a FM mobile radio:
The Kenwood TW4000-http://www.universal-radio.com/catalog/fm_txvrs/tw4000aL.jpg
That brushed aluminium front panel is just beautiful, kind of like a FM version of the Kenwood 599 twins.
The Kenwood TM201A is in the same category: http://www.universal-radio.com/catalog/fm_txvrs/tm201aL.jpg
The B version of the TM201 wasn't nearly as pretty.
The most interesting has to be the Standard C-50: http://www.rigpix.com/standard/c50.htm
Does this look like a home stereo receiver or what?
The Standard C156A wins hands down: http://www.rigpix.com/standard/c156.htm
I have had a couple of these, they are the classiest looking HT I have ever seen. Just a perfect fit and finish and they feel really rugged as well.
Hononable mention to the Icom P2AT: http://www.rigpix.com/icom/icp2et.htm
For some reason I just love the look of it. The Yaesu VX7R (silver version) also looks very nice.
For HF rigs:
I have to agree with the Kenwood 599 twins-any model of them. The 599 and 599A almost look like chrome front panels.
The Heiberling PT8000 also looks nice with a blue (!) front panel: http://www.rigpix.com/hilberling/pt8000a.htm
I also like the Yaesu FT107 that someone else mentioned.