For the money my Quicksilver Audio Mini Mite tube monoblocks. I’ve had mine for 18 years and for $998 US dollars (in 2006 dollars), they remain the best dollar to performance value I have spent in this hobby. As Sam Tellig wrote in his 2001 review of the Mini Mite monoblocks, sound does not get much better. You can spend alot more money on more powerful amplifiers but you won’t get much better sound than the Mini Mite monoblocks no matter how much more you spend.
The other great audio value for me is the DNA Starlett headphone amplifier for about $2000.
They are a limited production product offered by Donald North Audio and I believe the latest price is about $2500 US. Still worth the price IMO.