-Effective (i.e., non-destructive) Cottered Crank removal (and re-usage)
-ways to prevent cold weather pawl freeze up in cassette hubs
-Cheap lights for bikes (I've heard tell of some creative holiday string-light setups)
-ideas for rust proofing/rust prevention concerning steel frames, spokes, hub bodies, etc... the stuff that typically looks drippy and nasty.

There is a physical problem with lights that are not powerful. As we humans get older our cornea become harder and do not open and close as quickly as in our youth. This leaves us blind to all but the brightest lights after we are hit in the face by car headlamps. I witnessed a cyclist disappear when he was backlit by car headlamps. He had a few $15 to $20 front flashers, a reflective vest, and reflective tape on the bike. Once he was back lit by a car all those inexpensive low wattage lamps were worthless to his safety

If you do not invest in a bright light you will disappear when back lit and in other situations. The lesson I learned is simple if you are to be traffic at night time you need to act like traffic. If you can get the Cat Eye 520 at cost, it is about $30 and well worth it. 1200 candle power is close to the brightness of a car head lamp, 300 hour burn time with 4 AA batteries. When in traffic, act like traffic. If they are well lit, you should be equally lit to be seen. A flash light is not enough.

I am not saying do not have fun with cheap lights too. I look like an alien space craft with all the cheap lights around my bike. I also have a serious head and tail light. I do make a spectacle of myself out on the road at night. Have fun and think about safety.