There’s a Starbucks in Washington that has a bicycle powered blender and the customers make their own drinks or something (I couldn’t find any information on why they’re doing this or which one in WA, but there was a video on Keith Obermann last night). So, here are some resources around the web on bike blenders, seems pretty easy to make a DIY version.
Byerley Bicycle Blender (they sell a bicycle blender) – Link.
Bicycle powered soap blender – Link.
Bike blender for margaritas – Link.
Plans for Pedal-Powered Vegetable Juicycle – Link.
And here’s a story about someone making ice cream with a bicycle powered ice cream maker – Link.