Greatest Thing Since Duct Tape
Don't let Amazon's placement of it in the "craft" section fool you. E-6000 is the best all-purpose, stick-any-two-arbitrary-things-together adhesive I have ever found.
I made my daughter a Christmas present which was a reproduction of the painting in the Disney Haunted Mansion where the man in the picture slowly turns to a skeleton. I will post a build report at some time, but I had to anchor a heavy computer monitor to a wood box and an Ikea plastic frame, and E-6000 welded the whole thing together. I also have used it recently to glue studs to a concrete floor to support a cabinet and to put a rubber weir under my garage door. It takes a day to cure, and will not go on thin and sometime can be messy, but it makes an awesome bond. I almost never touch epoxy or Liquid Nails any more.
Update: I know Gorilla Glue has its adherents. The problem is that it expands so much (it kind of foams), it is really hard to control and get good results, at least in my opinion. Neither of these replace ACC when you need to bond something fast or when you want your fingers stuck together all day.