During my senior year at NJCU, I took a course titled "Workshop: Writing the Memoir." Interested in non-fiction writing, I signed up for the course. Needless to say, I learned a lot from it and enjoyed myself immensely. One of the things, however, that I took from the class that is still with me, is the 100 word group.
100 groups are made up of seven people--one for each day of the week. Each day, someone writes 100 words based on a word, phrase, or idea present in the previous day's 100 words. The 100 words can be in the form of poetry or prose. Doesn't matter.
I find this activity helpful because it generates writing activity on a set schedule. Although you should be writing everyday, you probably don't. This ensures that at least one day a week, you're writing.
I am part of a 100 word group. I don't generate useful material a lot, but sometimes I do surprise myself. So get six friends together and start a 100 word group!