You can E-Mail me at: email@example.com. I get a lot of E-Mail, but like to try to answer people who write to me personally.
If you wish to send me professional tech-related E-Mail, I suggest E-Mailing me at jmallett@FreeBSD.org for FreeBSD-related messages or firstname.lastname@example.org for anything else. Note that I get an awful lot of bulk, unsolicited E-Mail from recruiters who are using a shotgun approach to finding people; I don't typically respond to those messages unless I can direct said recruiter to a friend in need of work. If you write an original (and ideally interesting!) message to me, I will try to get back to you.
If you know me personally, @caladri is the best account to follow. If, on the other hand, you're acquainted with me through my open source, professional or other technical work, you should probably follow @vmjulix instead. The difference is mostly down to the nature of the ephemera and the amount of swearing.