I can be contacted via email by using either PGP or S/MIME; two systems that allow for securing email contents from being read by third parties.
OpenPGP is one of the most popular protocols for securing email. It is free to use for everybody and while it may not be quite as easy to set up as Jabber is, it is also not terribly difficult to use for someone who knows some fundamentals on IT. Personally, I think the easiest way to use it is to combine Thunderbird and Enigmail. See the guides above to get started.
A popular alternative to OpenPGP is S/MIME, which is supported in most popular email clients and which therefore
does not need installation of any new software.
One of the main differences between OpenPGP and S/MIME is that the certificates (corresponding more or less to the keys in PGP) have to be "signed" before they can be used in e.g. Thunderbird. This can be done for free (which is what I did) using a service such as the one that Comodo provides. Moreover, one can simply sign ones certificate oneself, but not all email clients accept that solution. Personally I use S/MIME primarily to contact various Danish authorities, which is something one unfortunately has to do constantly when leaving the country.
Can't I just have your email address?
I used to simply give people my email address and let them decide how to use it. That actually also worked completely fine for the most part but in recent years it has become incredibly popular to use email providers, such as gmail, that have admitted that they read through all the conversations that pass through their cables; also for Danish users even though it appears to violate the Danish constitution (article in Danish). I can't say if it is illegal or not, but I personally do not want to be a part of it, and securing one's communication using one of the above approaches is the easiest way out. Besides snooping email providers, this also provides some protection against eavesdropping governments and other IT criminals.
If the above is too inconvenient, you can also contact me via email by using this contact form, but please be aware that this leaves me with no way to reply in a secure fashion. A different alternative is to contact me through Jabber which is also a lot easier for newcomers to set up.