Try this one.

http://www.amazon.com/Streamlight-Sc.../dp/B00008BFSF

My father-in-law (literally "in law" - He works for the Sheriff's dept) has one of these. It's about twice the diameter of a Mini-Maglite and the same length, but it will put a 2-3 C-cell Maglite to shame.

If you are looking for something with some girth, go with a D-cell Maglite instead of the C-cell.