Anyone ever used anything like:
(for background, I went to quote an exiting client on a IT fit for a new office. The initial pleasant surprise was that it already had a full structured cabling system in place - concentrated in a nice big equipment cupboard. then I noticed in decommissioning the previous owners kit some muppet had hacked through all the CAT5 cable about 2" above where it went down through the concrete floor, with not quite enough slack to get a patch panel in at a low level. Hence it means either re-cable the lot (which seems like an expensive waste of effort), or find a way to splice on extensions to the cut cables)