If you are in the mood to see what baseless lawsuits can allow companies to continue to do in the United States due to our slow court system's inability to handle these lawsuits promptly then check out this.
For those who don't know the details of SCO's case against IBM and potential baseless lawsuits against Linux users, this link won't help much but it definitely makes SCO look dumber if you are an experienced C Programmer. SCO is continuing to make less-than-intelligent claims of Infringement within Linux with their latest "proof" related to the header files, specifically errno.h, a header file that is a definition of error numbers and is a part of the C Standard Library as well as public domain.
Funniest part of it all, being that Linux is an open software with EVERY change documents, Linus Torvalds has already made clear he wrote the original version of another header file SCO is claiming copyright of HIMSELF. He can outright prove it as well.
Signing up for a hosted IP PBX provider is just like signing up for cable TV; the provider is trying to lock you in to a long-term contract at terms that give them the most profit, while you're just trying to get the service and features you need at the lowest possible price. Plus, there are always hidden costs.