PVC and vinyl tubing are super-useful not just for their original plumbing or electrical applications, but for DIYers and ID students seeking to cobble things together with a relatively inexpensive, easily-workable material.
One potential issue is how to get clean, square cuts on the end. For vinyl tubing we looked at this clever DIY cutting system. For more rigid PVC, a miter saw does well, but it can be awkward for long pieces, and there may be times when you prefer to bring the tool to the work rather than vice versa.