An admin post à la "what do you think about that" will not work in a rather inactive community. It's not that bad like "why is this board dead", but all you'll get are some replies like "yes, you're right" or "no, I don't think so".
This may sound a bit fishy, but in fact it is a good way to create real topics on your board.
Of course you can't apply every "rule" to all communities, but the basic community dynamics are the same in most cases.
People will post more if they are upset about something, therfore, if you check the boards of all major software companies you will find tons of people complaing about their products. This of course is mostly because of very bad community management. But it gives a small insight into community psychology. You don't want them to get upset about you, it will create a bit more traffic on your board but it will come back to you very soon as the community will fall apart.
One of the best methods is creating a controversional topic that will splitt your community into two or more groups.
You may go "undercover" and post some rather provocative messages. Keep it relevant to the topic though, the last thing you want to do is starting a rant-thread or a flame war on your own board.
