Gallery walls are such a great way to display a variety of items. Not only do they look good, but they add such interest and context to a space. For me, the best gallery walls combine a mix of artwork, photographs, mirrors, and sometimes other three dimensional curiosities (such as antlers, or box frames and shelves). I also find that they're a great way to display artwork or goodies that you've picked up along your travels - it reminds you of your trip every time you walk by!
Here are some that I'm loving right now: