I took a regular keychain lanyard I was given at a bar and turned it into a belt. I thought I was pretty clever myself, and since I haven't found anything similar while browsing the interwebs I thought I'd share this easy peasy craftable.

First I used a seam puller to separate the buckle from the rest of the fabric. There are two “sections” of fabric: the lanyard attached to the “female” part of the buckle, and the smaller bit attached to the “male” part. After removing the buckle from both, I sewed the two pieces together to create one length of fabric. I purchased the sliding piece for adjusting the size of the belt from a fabric store (a package of 2 is less than $2) and after a few minutes of tooling around with it was able to make it slide, in a manner that was logical to my inferior intellect. Once the sliding piece is in place, I attached the male and female buckle pieces to their respective ends of the fabric, sewed and voila! A fancy, one of a kind, make your friends jealous of your creativity belt! :)