used to assign distance to the subject - either to avoid going into detail, or to suggest a lack of knowledge of it. also can be used as a noun.
1. "there were about a dozen people at the party - Betty, Sue, Wilma, Christine, Peter and I, and about half a dozen random others."
2. "I didn't pull last night, but when I left, Stephen was getting off with some random guy."
3. "Nice party. Who are all these randoms?"