The Konova Roller bearing slider is still one of my favorite Video Camera sliders, but with demand comes rising prices. The IGUS linear guide rails are no secret and are extremely efficient for the price (Much better than the $99 dollar 80/20 aluminum extrusions). For anyone looking to DIY an IGUS rail as a camera slider, there's some options available via Amazon. There's still some fine tuning involved like adding a brake/stop, drilling a hole through the carrier, adding some stands, and threading some mounting options for your tripods. Not a project for everyone.
Here's an interesting recent DSLR Slider item listed. Opteka's released an entry level portable IGUS based camera slider with FREE SHIPPING. Opteka's got all the necessary pieces and features you would normally have to DIY yourself. Included in the cheap slider is threaded taps for your quick release plate, pre-drilled Fluid Head hole in the carrier, a Brake/Stop screw, a few added legs to set it off the ground, and an included Spirit Level. So if you've been thinking about that DIY IGUS setup, but were afraid to tackle the details, you might want to check out Opteka's version available from 23' to 47" length. The Manfrotto 700RC2 Fluid Head would work great on this small slider as well.