How to introduce myself briefly in a get together for new faculty members?

Partly, you'll want to copy what others are doing. If everyone else only talks for 15 or 20 seconds, then almost anything that you say in a 3-minute monologue will be poorly received. Information that you'll likely want to mention includes: name, department, research interests, possibly where you've just moved from, and maybe a bit about you personally (I enjoy triathlons; married with two kids; active in a barbershop quartet; etc.) One point about your research interests: keep it very nontechnical. Rather than give many details, say something like I write computer programs to help blind people use computers, or I study 18th century literature, particularly the works of SoandSo. Most likely, this activity will be pretty informal. If you're still a little nervous about it, you might ask another junior faculty member in your department.