You could get an under-sink reverse osmosis filter, they're about $150-200 on eBay.

If you don't want to go the reverse osmosis route which is super easy, then even easier is a tabletop distiller. I distilled my water when I lived in Vermont and there wasn't room under the sink in the apartment for the RO. A tip for distilling: put it on a timer to have it automatically go off when there is still a little liquid on the bottom - it won't build up as much crap to have to clean off. You will have to figure out you own timing on it, but it's much better than descaling it. Don't let that bit of stuff touch your skin though. It is nasty or at least was on Burlington. Smelled horrible.