One of the things that I have only done once... but I would LOVE to do again and again until I perfect the technique, is called Star Trails.
My camera is a Canon 60D. There is a way to "hack" the Canon DSLR's so that they get some amazing functionalities, such as taking a picture just by clapping (really cool for when you want to take a picture and no one is able to push the button) and taking pictures at certain intervals.
You can read more about this "hacking" on
Anyways... So in May last year I went to the mountains and I took pictures of the stars... every couple of minutes, the camera would take one picture. I just let the camera do its thing and went to sleep in the car. 2 hours later I stopped the camera, and the next day I post-processed them into star trails.
I used this program to "stack" the pictures:
http://www.startrails.de/html/software.html
Here are some of the pictures that the camera took, no editing:
And here is the final result, once the program stacked all the photos and I tweaked the pic a little:
I loved doing this, I loved just watching the stars and this mountain and feeling the peace. At the time I was saddened by the process of learning TTATT, but this helped me find some peace.