You are a few upgrade generations back. RaQs were retired in November of 2004 XServes were retired in June of 2006 Blades were retired in May of 2013
Yep... the one RaQ 550 is still there, but it's not doing anything (no sites, no database, no mail, no nothing)... Thing only draws a tiny bit of power, so I just never bothered to unrack it. The XServes are still there too, but the only thing they do is act as a backup destination. The blades were pulled out of data center because they were 220V and sucked so much power it was crazy... so definitely didn't want to leave them there.
If you want to leave the raq there and not want it to draw any power at all, the why not just unplug it?