I use fonts by Kevin and Amanda in my designs (headers, buttons, sidebar titles, etc.). They have tons of fun fonts to choose from, including an entire line of handwriting fonts.
Fonts by Kevin and Amanda can be used on commercial blogs and Etsy banners for an additional $10 licensing fee.
Have a specific font that you'd like to use that was not made by Kevin and Amanda? Email me. Chances are I have it or can get it easily. :)
At this time, I only use Century Gothic and standard Blogger fonts for post and sidebar text.