<p>For hanging things on the wall-- my alltime favorite, most recommended tip is to use the 3m Poster tape. It comes in a roll and is slightly thicker (and more heavy duty) than your average double stick tape. It works like an absolute dream. My second favorite thing to use, especially for larger, heavier posters, is velcro which can be found at BBB, L&T, etc. The sticky tack tends to stain walls and has only worked for me when used with other things.</p>
<p>Honestly, I see no harm in nailing things to your walls. No one is ever allowed to do it, yet people always seem to. MY RA simply told me to cover my nail holes with white toothpaste at the end of the year, and then I'd be fine (and I was! I nailed things and got no end of year fine). Also, I've seen groups of friends, or RA groups on hallway invest in a small jar of patching plaster at the end of the year to fill in nail holes. Freshman year I had hung a framed picture with plastic hooks which a) looked tacky and b) left a stain so I wound up with a small fine, last year was so much easier with the nails.</p>