From http://www.chicobag.com/, these convenient reusable bags pack down smaller than your computer mouse in their own integrated pocket. They even have a little carrabiner if you wish to clip it to anything. Toss them in your backpack or messenger bag for those spontaneous trips to the store, then carry them in your panniers, basket, or hands on the way home (...or if on a tandem, make the rider in the back do all the carrying!) Cost is $5 each and multiple colors are available.
Made from recycled bicycle components, this keychain opener from http://www.resourcerevival.com/ comes in multiple colors and runs $14. This is a perfect stocking stuffer for most cyclists because when they're not thinking about bikes, they're drinking about bikes.
Enviro-lube:Dumonde Bio Green chain lube is 100% plant based and biodegradable. It's a green lube that actually works. Get it for $10 at http://www.rei.com/.
Hopefully, your holiday shopping is wrapping up (so to speak) and that you have plenty of bike-related gifts. Keep an eye out for the next installment of the Gift Guide!