Lately, I've been encountering more and more people who want to participate in open source communities (and other online communities) but seem to be afraid of having their email address posted anywhere on the internet out of the sheer terror of drowning in spam. Given how easy it is to setup an extra email address, why not just create an extra account and use that for your public address, saving your "private" address for your friends and family?
I've had the same email address for over 10 years, and according to GoogleBot, it's listed in at least 960 places on the web. According to Gmail, I get about 1500 spam emails a day, and Gmail catches about 99% of them on any given day, which is extremely manageable (thanks, of course, to the extremely hard work of Brad and his team). Does Gmail get any false positives? Maybe--I just don't have time to go wading through the river of spam to check (54,061 at last count). Long ago I decided that I'm OK with any false positives that get through--if someone really needs to get a hold of me, there are a number of ways to do so.
In short, if you want to participate in online communities such as open source projects, just setup a "public" email address, use that, and don't live in fear of getting buried in spam.