Updated January 15, 2012.
Payments for auctions, or simple monetary donations (which are very much welcomed) can be made through PayPal. Click on the button below, enter the amount, and click "Update total." Then pay by logging in to PayPal or through a credit card (you do not need a PayPal account):
On the "review your donation" screen, click "Add special instructions to the seller" and indicate whether this is a donation or payment for an auction item. If it's an auction item, also specify the seller & item. If you can't fit all the information in that field, just note that you'll e-mail with the details, and forward your receipt & the auction information to email@example.com. This way I don't annoy you and embarrass myself by hounding you for payment. (There's no need to forward me your receipt otherwise, I get it automatically.)
If for some reason PayPal is absolutely impossible, please contact me to see if we can work something out.
Non-monetary donations, such as convention memberships, can be made by e-mailing me (again, firstname.lastname@example.org).