Buying Toribash prime costs $10 a year, it allows you to change your forum title, e.g. mine is "Now made with real fruit juice" and add an image to your signature.
You have to buy Tori-Prime Which has more benefits than just being able to have a Sig.
These benefits include changing your title above your avatar (Junior Member, etc.), enables more characters in your signature, and the ability to upload a 400x150 picture as your signature.
Threads which involve simple quick questions should go in Rapid Threads.