You post a "Top Five" topic, list, category, whatever, in my comments section. (examples: "5 Draco and Hermione Didn't Kiss, But They Should Have", or "5 Things Bones Never Told Jim"). Then, in comments, I'll post the answers to all your Top 5 ideas, according to me. Serious or fun! Then you post this offer in your own journal.
Only offering this in Harry Potter and Star Trek (except for Ree, who can request anything, and maybe Tabby, if you have something really cool, m'dear).