Clear varnish for textured coat

A while back I built a pinewood drafting table for myself. The mechanism works great but I find that papers, books and my laptop sometimes slide down the table. I don’t want to coat the table with a thick paint or a mat because I like the look of the wood. However I am looking for some type of clear varnish or finish that will stop things from slipping (in the same way that some slanted desks have a rubbery surface)