What different accessories make your riding better, more fun, more productive, or are just nice to have?
Here is one I use all the time. It folds into my wedge or my jersey pocket. Often I get a call to pick up some fruit or something else at the store. I can carry almot 25 pounds. Or, as I peel off layers, I get this out and stuff the layers inside. About $10 - I have one on each bike. It is very small and becomes pretty big as it unfolds into a back pack with shoulder straps and all. Kiva Key Chain Pack.
Any other accessories, etc.? Please share!