mmmcrafts.blogspot.com streamlines her jeans to be skinny. I have at least one pair that need this treatment but am pensive about modifying jeans! I have avoided due to the specific thread, needle, and patience needed; but darn it she makes it seem easy; and I swear she's wearing my boots!
Tutorial: How to Resize Your Jeans to Make them Skinnier. Full tutorial with picture to show you how to make skinnier (or skinny) jeans- without twisted legs. A must read if you plan to take some jeans in.