Okay I can't say it's a hobby I don't find absolutely fascinating.
I was seriously going to study astrology properly and do this compatibility business for fun on the side...until my astrobro(a professional) discouraged me from investing in doing so because to do all the calculations from scratch is seriously hard work and hardly worth it when with most programs these days the information is readily available with the press of a button.
In any case if you really understand astrology, it's a seriously powerful tool to understand people and predict their behaviour....saving all those wasted tears, hair pulling episodes and spilt milk. The way I came to learn astrology was very much personal...by being a fly on the wall doing what I love best, saying nothing and just observing everybody I've ever met and sticking them into my mental database. It was not until I was fairly old that I became familiar with the star signs and read all the masses of stereotypical information you find online, which is not half bad actually, lol.
In any case, people too readily dismiss astrology as a load of crap...that's cos they don't go deep enough into a chart. For example, although I have a Scorpio sun, I have so many planets in Libra that I'm a very Libran Scorpio- most people read sun signs without paying any attention to these important nuances which have a huge influence on being able to accurately size up a person's character.
Over the years I've started to fine tune this to a bit of an art, combining eastern, western astrology and numerology with my own rather large database of detailed observation. I just noticed this is one rare "fad" that has been able to withstand the test of time with me...I doubt I can ever get bored-it's too much fun! :)