Now, in order to get the LED's to work with the condoms, I've found that the following shape works the best in order to get good, consistent contacts. One thing as well, you might want to wrap some electrical tape around the wire in between the resistor and the LED. I was testing one LED once I got it into the condom, and the lead got folded over until it was touching the wire between the resistor and the LED... so bye-bye LED.
Oh yeah... for testing I used a 9 volt battery that I've taped wires to the + and - leads... makes a really handy tester!