Which folder/file are "Item Sets" saved in?

"Item Sets" are a really big improvement on League of Legends client, but the data is saved on the local disk.

I want to backup my file/folder, so I can (hopefully) transfer my builds to other PCs. Copying the entire LoL folder is impractical (more than 4GB).

Which folder/file are "Item Sets" saved in?

Solution 1:

{your install dir}\Riot\League of Legends\RADS\projects\ lol_air_client\releases\0.0.1.16\deploy\preferences\{your name}.properties

NOTE: 2013-05-18 latest patch it's now "0.0.1.18"

This is the location and filename of the file that gets edited whenever I change an itemset. This is of course only as current as of today and might change with newer patches.