I think it would be awesome if there was a feature which took into account your activity on the site... and did a search to find (as if by magic) questions you could answer.
(Apologies if this is already suggested, It seems so obvious, but I can't find it.)
Criteria for the algorithm may include:
- lack of existing answer
- number of answers you've given on similarly tagged questions.
- number of questions you've asked on similarly tagged questions.
- number of upvotes you've received on similarly tagged questions.
- (all of the above but replace 'similarly tagged' with some kind of keyword matching algorithm.)
Perhaps there's even a real fancy neural network or something you can do this with so you don't have to work out the weightings.
Also, add notification so you can get in quick and answer :-)