I am a photographer and experiment a bit with lighting, in particular, I am using LED's in the place of a standard photography flash...my current build consists of one hundred and forty and change watts. Besides, I got that 50 watt monster (one of two I have) for three bucks. You would be surprised how cool (comparatively) it runs. When heatsinked, you can put your finger directly on the emitter and it is only warm.
I admit I am a junkie for blinkie lights... You know, I also forgot the 72watt wall wash RGB LED's, color mixing done with an Atmega8 running Arduino code. It also uses the internal RC clock at 8mHz, so there's no resonator or crystal, the whole "arduino" is the ATMEGA8, 7805, and a couple of caps. I'll be writing the build up sometime soon.
I tend to bottom feed on ebay for cheap components.. Sometimes you get a great deal because something just slips through the cracks and doesn't get bid up. For example, since I had them, I included three 5k linear potentiometers for color adjustment. They are from a ten pack I got a while back for something like a dollar and a half, some wholesaler on ebay. Fifteen cents each, nice quality. Granted, that is a fluke, but I have long hours to go fluke fishing..
I have probably a hundred and fifty NPN standard transistors, 3904 and 2222 mostly..
Thirty logic-level N channel power MOSFETs
A dozen TIP41c and half a dozen TIP120..
a half dozen ULN2003 arrays.. And a handful of assorted SCRs and TRIACs.
That's the transistor drawer at the moment...