Besides my scientific interests, I have two other big passions: travel and the outdoors. These usually take up a large part of my non-professional life. And when I'm not working, traveling, or hiking around somewhere, I like to read books, listen to music, or escape reality by drawing fantasy worlds.
Travel
My work has literally taken me all around the world. I generally try to arrange short-term projects in different places so I can work and live in a new country for a while and really get to know its people, culture, and nature. And once the job is done, I usually spend some more time just traveling around to see and experience a bit more of the country I happen to be in.
The great outdoors
My love for the great outdoors came relatively late in life. But once I had found it, I never let go again! I usually spend a large part of my free time hiking, trekking, snowshoeing, or (formerly) mountain biking around. Especially the mountains have a big attraction for me, but I generally enjoy any kind of natural beauty, whether it is lush forests, dry deserts, empty beaches, roaring rivers, or deep canyons. Being out in the wilderness is one of the best things in life!
Music
Besides traveling in the "real" world, I also like to make musical journeys. My taste in music falls mostly in the symphonic and progressive rock categories, with obvious bands like Pink Floyd, Genesis, Yes, and Marillion, but also bands like Camel, Ozric Tentacles, Focus, Bozzio-Levin-Stevens (and more), which are less well-known outside of ProgRock circles. In the classical genre, I mostly listen to piano music (Beethoven's 4th & 5th, Rachmaninov's 2nd, and Tchaikovsky's 1st piano concertos are some of my favorites).
Art
I'm a big fan of surrealism, metarealism, magical realism, and fantastic realism. Some of my favorite painters are Salvador Dali (of course...), Johfra, HR Giger, Bob Venosa, Roger Dean, Carel Willink, Diana Vandenberg, Michael Whelan, and a bunch more. Inspired by all this, I used to do quite a bit of drawing myself. Please have a look at some of my personal drawings.
And then some...
I'm a vegetarian for a combination of health, ethical, economical, and ecological reasons. I enjoy doing yoga (Hatha), even though I'm about as flexible as your average lamp post (but it feels great anyway). And I like the original Buddhist and Taoist philosophies of life (but not so much their religious derivatives of empty rituals, superstition, and dogma that all religions have fallen victim to). Well, I guess by now I have no secrets to hide anymore ;-)

Life's just a show for free; come along and watch with me.
---Supertramp