Make a remote shutter release for your canon digital camera (and some other brands such as Pentax, sony, and some nikons) for about 3 bucks in under 5 minutes, even a 1st grader can do this. This is great for getting the perfect exposure, and enables you to go past the 30 second exposure offered with canon cameras. I use this on my Canon Digital Rebel SLR and it works every time...
Step 1: Hands Free Phone Headset $3
First you'll need a "hands free" headset for phones, Make sure it is one of the kinds with a button about 8 inch below the ear piece. And make sure its a 3/32-inch (2.5-mm) plug (like the plug on a pair of Regular headphones, but one size smaller). I took a pic next to a quarter so you can make sure its the right size. Usually anything for Motorola phones should have this
I found one for $3 at a store called Big Lots (its like a step up from the dollar store) and better yet my g/f works there so i got 20% off!