Interested in getting started with a Smalltalk application server? You can try out VisualWorks and Gemstone in their NC forms free. VW on a single CPU starts at $6000, and Gemstone has just introduced a starter package at $7000. So you can build fully network and web enabled server applications - including a nice persistent store on the back end - for a combined $13k. That's very competitive with the Java app servers. Have a look!