One, To Rule Them All
When I first saw a wiki, I was awed by its concept: 1-script == complete website, editable by anyone browsing? That's soooo kewl!
One thing though, for me, is how easily a wiki site gets out of control. A link, a page, another link, another page and since wiki manages the links without regards for hierachies.. it takes on the properties more like a mindmap and becomes a mess of data, with creepy crawlies lying in many dark corners. When my wiki becomes a monster, I get turned off and start afresh.. loop. I still use wikis, only these days I use Instiki and for specific and limited purposes only.
There's another mess is waiting for me. Java frameworks.
Struts, Tapestery, Maven, Spindle, Tacos, Spring, Hibernate,... e.g. Just look at the projects and sub-projects here. Don't get me wrong, I love the Apache Foundation. But, though an abalone is a delicacy.. too much will still make you puke. All these overlapping, 75%-alike, distant-cousins frameworks just makes my head spin. Perhaps dictatorship, e.g. Linux, .Net, is still the best way.
The blessed birth of Rails is in that the Ruby community now has only 1 hero to look for.
Whereas in Java-land, the best thing to do now is to pick those projects (that suits ur needs) with the most momentum and ignore the rest. Reinventing the wheel? I'd rather risk that, than to read through every new wheel.