Add something visually interesting to your bathroom tile by interspersing small strips of another building material into the design. Here we see rocks encased in cement. Shells or jewels would be another great choice.
Choose several different types of tiles in complimentary colors. Add a single bold color to really make the tile unique. Here we have sandstone colored tiles that are made bolder by small copper tiles (and fascinating tri-tile design).
Mix small and big tiles. The tiles on the wall here show off a great example of using smaller tiles around trim and mirrors to create a pleasant design while using larger wall tiles to make up the bulk of the wall.
A narrow strip of tile that runs from floor to ceiling along one wall can provide a really fascinating texture and color for your bathroom. The tile here is fairly neutral but you could feel free to go very bold since this is just a small portion of the room.
Don't be afraid to choose a very bright color for your bathroom tile. It's the one place in the house where you can really go wild without overwhelming the home.
Boldly patterned tiles can be combined with a few statement pieces (like this mirror) to offset the severity of dark cabinets. Bold tiles work best on bathroom walls but can be used on floors as well.
The right tile can be patterned in such a way as to create an abstract art look for the wall of your bathroom. Here we see a "rising sun" in the tile pattern. This is great for large bathrooms like this one that also have seating or relaxation areas.
Use mirrors to reflect the tile in your bathroom. This is an example of how you can create an amazing optical illusion with high mirrors and colorful tiles.
The shower is my favorite place to play with tiles in the bathroom. A luxuriously-tiled shower creates a much more spa-like experience than a plastic or cheap ceramic shower does. I love the way this shower uses four different tile styles (shape, size, direction) in the same color scheme to create a playful space.