Pros
Lots of opportunity to do everything, since the company was so small (at the time). True to the software startups, I got to do everything - answer the phones, migrate our email server, do tech support, work on improving our product/company in search engine listings, and if there was time - actually work on product software.
Cons
Since the firm was so small, I had to wear many hats - some of which I didn't really want to do, like answer the phone & handle customer questions about how to use our products. Also, the pay sucked. This is definitely not a path to your career in software; this was just a way for me to get something on my resume so that I could actually land a real software job (which happened about 3 months after I started this job).