Web services I asked Redhat CEO Mathew Szulick where he thought GNU/Linux was going in the enterprise, and he said "operating systems follow applications." Three days later, Google releases it's search appliance and with it, the clearest example of an application server. Application servers:

• Deploy over LANs because of security and bandwidth constraints
  
• Simply provide a service while playing well with others
  
• Run on GNU/Linux

Very nice. I wish I had info on pricing.