However the pain points that you actually should solve are the ones that drive you crazy, that make you woof in annoyance when they just don't work. Stuff that you know you 'should' do but find a way to put it off. People tend to stay away from these areas because - well they hate them!
Yet that is where the solutions are needed the most.
Some pain points that really frustrate me :-
* Getting an e-mail with an attachment that I have to print out, fill in, sign, scan back to my e-mail and then attach back to the receipient. That is just far too many steps. I don't think the likes of 'Sign Now' cut it because that relies on the sender sending it in that format. It needs to be a solution for the recipient.
* Setting up mailing lists.
* Formatting & nice templates for e-books.
* Following up enquiries x number of days after I sent a quote.
* Tracking the ROI from different advertising methods (adwords, print advertising, facebook etc)
* Tracking all the issues & bugs I fix at work to prove my productivity.
Don't pick what you WANT to work on. Pick something that is currently a pain in the ass and feel the benefit of your own solution.