Yet another great picture hanging idea. Place a length of masking tape along the edge of a spirit level and mark the location of nail holes for your picture frame. Then simply transfer the level to the wall to ensure you hang your pictures straight.
Safely pack your razor with a binder clip & 13 more travel hacks to make life easier when traveling - one time I didn't and I was rummaging in the dark. The next morning I had blood all over me because I'd cut my fingers and didn't even know.