If it's your first Lonely Prompts day, what happens is you rummage around at Delicious in the Lonely Prompts area. If you see something you like there, fill it!
Please post a link in the comments here if you fill a prompt. It helps the code monkeys (and someone else might want to see that particular prompt filled, too).
At any rate, for those of you celebrating, happy day-before-Christmas Eve, and I hope to see some prompts filled today!