Do you mean 100G? 10G has just worked for many years, as long as you have relatively recent cabling (cat6). There's also 5G now if you have old cabling (https://arstechnica.com/gadgets/2016/09/5gbps-ethernet-stand...)

Depends on what your idea of relatively cheap is of course - low end 10gbase-t switches cost about $200-$500 (cheapest ones have just 2 fast ports and rest are 1G). NICs are about $100.