Stuff that works directly with a laser printer will have the kinds of problems described in Gwyn's answer. If you have access to an inkjet printer, you will be in business. There are clear, printable vinyl sheets that stick to a wall or window with static electricity. The media will melt in a laser printer, but they're coated to accept inkjet printing. They can be used with laser printing in a different way, which I'll describe below.
Some only work well on a smooth, glossy surface, like a window. Others will stick to most walls as longs as they aren't textured. Here's an example (no personal experience with this product):
These are commonly used for temporary signage.
This picture looks like white media because it is used with laser (or other) printing by gluing the laser-printed sheet to the cling sheet and using the cling sheet only for adhesion. If you need it clear but laser-printed, you could print on laser transparency film and glue that to the cling sheet.
This film will stick to a window for a very long time, but I don't know how permanent the hold is to a wall. If you need it for more than short-term use, you could investigate its longevity in practice.