I had the same issue recently. What I did is sign a blank paper, take a pic of it with my phone and copypasted the text over the blank page with The Gimp.
I used to do that, but nowadays I tend to sign things on iPad. When using the stylus it looks exactly like it was hand signed (even without the stylus, I can just zoom way in and make it look kinda hand signed). The pdf is of course not scanned looking, but nobody had complained yet.
