Slim, revised variant of jridley's parametric ziptieless SCAD LM8UU holder.
I never liked snap fit solutions for parts that rely on precision. In particular the current Prusa design uses two different ideas for LM8UU holders which either lead to heavy warping of the whole part when inserting the linear bearings because of a very tight fit (e.g. x ends) or snap in easily (in case you don't brake them..) but leave a faily loose fit needing additional zip ties to fasten them (e.g. x carriage).
This is why I appreciate CdnReprap's attempt to have a pecisely fitting, yet tightenable LM8UU holder which can be disassembled as many times as you desire, leaving the bearings on the smooth rods.
Update V1.1 (2012-01-23);
* changed mountplate to be parametric too
* using polyhole function for LM8UU-hole in hope to achieve even better fit