A simple passive speaker for your bicycle using the parts you have lying around. Loud enough to hear on quiet roads. A person with very basic soldering skills should be able to do this; doesn't require any advanced electronics knowhow.
I made this because getting up those hills can be easier with some tunes, and I didn't have the cash to buy one of the commercial ones. I really liked this too because it recycled things that weren't being used anyway - go green!
Step 1: Materials Needed:
This instructable describes how I made my bike speaker. It's intended to give ideas for others to modify for their tastes/materials. It just uses what I had around and available; thanks to my friend Chris who donated the speakers that were just lying around.
Passive computer speakers (or active, but my available speakers were passive). The ones I used were branded Creative, and they were made by Cambridge Soundworks, so they were good quality. This helps.
Screwdriver - mine required Philips Head
Cassette tape case
Glue gun (or sewing implements, if preferred)
Mesh/screen to protect speaker