Not specifically ME but yeah Baseboard Management Controllers and IPMI modules have been a thing for a long time. Most real server motherboards have them or have the facilities in place to accept them as an add-on module. It's not even just stuff in the $20k range; this $450 mini itx 8-core Atom-based storage server board has it: http://www.asrockrack.com/general/productdetail.asp?Model=C2... and it comes with a web-based IPMI console. You can turn the power on and watch it POST with a java web screen viewer, sending it keys as if you were sitting there.

Dell's add-in card to do out-of-band management is called the DRAC and it's been optional in their servers for about 17 years: https://en.m.wikipedia.org/wiki/Dell_DRAC