I started out with that idea (adding a "contribute to me" button), and tried to validate it.

It turns out that the people I approached weren't interested in a service to accept contributions if said service had significant fees, and I couldn't find a way to make those cheaper (moving money has a significant cost) and couldn't compete with Paypal Donate.

I still believe there's a market for it (you're an example :) ), but it's going to be tough to convince the content owners.