I've always had trouble loading Nikon cameras. It often took 30-50 tries. I would only get it loaded by luck. I've never had this much trouble with any other camera. Here is a video that helped me figure out how to do it. By using the fold over trick shown in the video, I got it to work on the first try.

http://www.youtube.com/watch?v=LqmTmtbpClQ

What cameras do you find hard to load? What tips can you provide to help others to not have the same trouble you had? Don't just limit this to 35mm still cameras. If you have a tip about another format or a cine camera, go ahead and post it. I only posted this in the 35mm forum because I started it with a 35mm camera. Mods, please move it if there is a better place for it.