Another Sidebox Like Manufacturers

In my products General, I would like to add another option for quick search, like the manufacturers.php. I know I will need another option in my add new products and an extra option under catalog in the admin. Is this possible?

Basically, I would like 2 sideboxes. 1 that says manufacturer and the other that may have something like "Size". I will input it like the manufacturers - Under add Manufacturer. I will add all of my sizes and then choose which size when I add my products. Essentially, on my main page. if someone wants to search by manufacturer they will choose that sidebox and vise versa.

The reason I need this is a lot of my products overlap into many categories.