I visited the California Cactus Center in Pasadena the other day and it was mind blowingly awesome.
It was fun seeing things I had never seen before. Cacti and succulents are such slow growing plants, in direct contrast to the instant gratification I usually prefer. I'm not sure why I'm drawn to them so much. I think they represent sun and good weather to me.
If you are in the area you should definitely check it out!