I like PmWiki quite a lot. It's easy to install, easy to customize, and it doesn't require a database. (Neither does Ikiwiki, which I've also used and liked.)
Edit: In response to the OP's comment, I have used BoltWire (check your spelling and your link - both are incorrect), and I prefer PmWiki. They are both reasonably easy to install and both pretty lightweight. I didn't dislike BoltWire at all, but I found PmWiki more fully-featured and easier to configure.
Edit 2: Since you mention in a comment on another post that you are using Debian, both Ikiwiki and PmWiki are available in Debian and pretty trivial to install using your favorite APT package manager. I would recommend that you try both out and decide for yourself.