I bought some of these LEDs on eBay:
____LED with G4 baseI used these in my florescent fixtures. They are very bright and will handle a wide range of voltages. They have an on-board voltage regulator so they will handle voltages from 10 to 30 volts. As mentioned earlier this can be a problem for TV reception. The ones I have seem to only affect the VHF channels. Since these have a G4 base they would have to be adapted to use a wedge base.
I also replaced most of my incandescent bulbs with LEDs. Here's a link to info on my install:
LED bulb replacement