I work with a guitarist who's quite adept with a looper and uses it to great effect. That inspired me to get one, too.
I had a blast with it for a few weeks but ultimately sold it after coming to the conclusion that it wasn't going to do anything for me creatively. Everything I created with it turned out overly busy, weakly structured and immediately forgettable. I couldn't see it ever leading to what I'd call a "song".
The point being that some will be inspired by a looper, some won't. But everyone should at least give it a go. If nothing else it's a fun way to keep your fingers limber between gigs.