my theory is that everyone can paint/draw, they just need to be taught how. I've taught at least 5 people who thought they had absolutly no skills in art and after the first 30 minutes they were amazed at how well they were able to simply draw.
hmmm.. what are some other indoor hobbies...
decorating the house (think martha stuart...minus the jail time)
magic tricks/slight of hand
hmmm, that is all I can think of for now... I'll be needing an indoor hobby soon since it gets really cold in the winter here so I want to see other suggestions
*edit* going back to the art stuff, you could find objects and make 3-D sculptures out of them. It doesn't all have to be on paper/canvas.