I liked programming in PostScript more than Forth because of all the additional non-graphic things it had. Look at the Blue Book ("The PostScript® Language Tutorial and Cookbook") http://partners.adobe.com/public/developer/ps/sdk/sample/ind... for some examples.
Many years ago I did a project with a lisp back-end, a front end in PostScript (NeWS/HyperNeWS) and C code gluing the two together - it made me appreciate than an interactive PostScript environment is surprisingly lisp-like.
Edit: This has made me wonder about a NeWS-like server sitting on top of OpenGL and using an interactive PostScript like language.....
I started my career with a Turbo C complier, a PostScript printer, and a government database written in FoxBase. I learned a lot of PostScript programming in order to generate the report we needed. I later got NeXTSTEP 3.3 which made interacting with PostScript a true joy.
I have often thought a NeWS-like server would be a fine replacement for a lot of web stuff.