Best bang-for-buck purchase you have made?

5 years ago, I paid a 5$ door charge to see a KISS cover band...I now know what its like to be a true die hard fan of something:)

Van Alstine amp and biro L/1 speakers. Best bang for any of the bucks I have spent. It was about $2500 total. :-)

I too started off with a pair of small Maggies. I've been hooked on Maggies ever since. When I upgraded to the 1.6's, I actually ended up making a couple hundred bucks selling the little speakers. How often does THAT happen?

Best bang-for-the-buck, that's easy. I paid $1100 for a pair of Sony SS M9 speakers. I have been saving for a pair of Wilson Watt/Puppies or a pair of Soundlabs. I had twice that money saved but after hearing the Sony's I'm not sure I need them anymore. These speakers sound so much better than I thought they would. I had the smaller SS M7a and I liked them, but the difference is not subtle. I'm glad more people don't know about these. If they did I would not have been able to get such a great deal.
The only thing I don't like about them is the finish so it's hard to complain! Sound is more important than cosmetics!
I also bought an SCD 777es from a guy whose store was out of business. I paid about 1/3 of the asking price.
I still think a pair of Purist Dominus IC would rank up there regardless of the price because they sound so amazingly good!!!