I run my miners in alongside my servers, however the new miners that are coming out now obviously have larger cooling and power requirements. It seems as servers get more and more 'green' our miners are going the other way.
Many colocation services offer in the region of 1/4 amp per U, which isn't much even for an average 1U server! Also most datacentres cant or wont offer space other than for rack mount equipment, however Im starting to see more an more companies move towards cloud hosting services which might mean more cheap slots available in 'local' datacentres.
I'm in the UK.
I have been pricing out colocation to run 10 antminers...which consumes around 34A of power and produces around 4kW of heat.
I have at least one colocation provider that says they can do this for 800CAD/month...I am still shopping around though.