Ive had custom shift knobs on my car forever. I first had an ichibahn, now I have a ractive (kinda cheap, 80 bucks).
http://www.toucanindustries.com/index.php?src=directory&view=products&srctype=display&back=products&id=56944&submenu=Ractive&category=Shift+Knobs&pos=45,15,63
Its really quite nice and doesnt get as hot/cold as my other one (solid aluminum). I will have to take a pic of it sometime, its only been in my car for about a month. Also, all I had to do was shave the shifter down to make it a little skinnier, not make it round, I also cut it a little shorter so itd look better.