Oh yeah, refunds:

all the more reason to include your username in the donation/email! Your username makes it easier for me to find the proper donation to refund! Catohagen included his username, and so I was able to quickly find the information regarding his donation. It's easier to give credit, it makes including people in beta lists easier, and it makes refunds faster.

(psst. thanks catohagen for including your username in that original donation!).