I had briefly contemplating what sort of silly posts I could write to celebrate April Fool's Day, when I sat down to write out some of them, I got a few sentences in and decided that they just weren't funny enough. Either I have very high standards, or I'm terribly unfunny.
The web is awash with April Fool's articles, comics, headlines and everything else, so instead I'm going to just give you a few useful links.
A couple of Twitter links
Besides the @hudsonci account, you can also follow a couple of Hudson's more notable (or was it notorious?) hackers, such as our benevolent dictator, Kohsuke Kawaguchi. Ben Shine from Yahoo! who's been working pretty hard on making Hudson prettier. Then there's John Ferguson Smart who's been working on a Hudson book. Of course I've tried to collect as many Hudson contributors as possible in the @contributors Twitter list.
Hacking Hudson
When starting to hack Hudson, it's useful to start by understanding how to build Hudson. If hacking Hudson's core isn't your cup of tea, you can always start with the plugin tutorial and try your hand at writing another awesome Hudson plugin. If you find yourself struggling to find out what methods do what while you're hacking, you can always visit the regularly updated, online Javadocs for Hudson
Communicate The two primary mediums for communicating with the Hudson community are through the mailing lists and the IRC channel. During "regular business hours" for the pacific standard time zone, you can usually get some decent real-time help or answers to most of your queries.
I'd list more, but I'm too busy reading about Google's nuclear weapons program. ;)