Well, once I got the LED's roughed out, I thought "Why not make this a little more handy?". So I added a simple LED tester and a 5v regulator. All three systems are running in parallel with a 9v battery mounted in the lid. Sadly, I have forgotten the exist resistance used for the LED tester, but I do know it's at a good solid point so I don't fry any LED's. As for the 5v regulator, this is used for breadboard projects, and again, has the hookups in the lid, with a switch to toggle it on/off with an indicator LED as well. The design of the regulator is that of sath02 (link). And unrelated to the circuit, there was also some magnets glued into the lid so I won't lose screws. Hopefully.
I can certainly upload the schematic I used, but seeing as how this is a very "add what you need and can" type of project, I just stuck with pictures and explanations.