LanParty for Light games like cs 1.6 and etc. Pre 2008 maybe 09 and 10 era you could run from your own pc, for multiple servers, just buy cheap 1156 motherboard (tend go to P55 as you may need to overclock it a bit) and xeon with 4c/8t and ddr3 atleast 16GB of ram.
Or new solution go for 2011 socket cause motherboard are expensive BUT you get cheaper xeon with 8/12C and much threads.