I don't know if you guys are familiar with Alex Cavalli, he's been designing headphone amps for many years, releasing his designs to the DIY community and then went into business making, what could be argued to be among the best headphone amps out there. They've always been very expensive though, until today when he released the Liquid Carbon for $599. The ordering page opened up this morning for a limited run of 500 amps. I know there was a rush on it as soon as it went live, crashing the site several times. I don't know how many are left, but I just checked the web page and it appears to still have a buy button.
If you're looking for an amp, or always wanted a Cavalli, check it out. I'm not affiliated with Cavalli Audio in any way, btw, I just really like his stuff and thought some of you'd like to know.
https://www.cavalliaudio.com/index.php?p=product_details&pId=11