SOHT (Socket over HTTP Tunneling) allows you to tunnel socket connections through an HTTP proxy. Restrictive firewalls often prohibit all outgoing trafic except for HTTP. This application allows you to tunnel socket connections over the HTTP protocol. This application consists of a server that serves as a proxy and a client which tunnels a socket connection over an HTTP connection to the server. The current server is written in Java, and there are clients in Java and .NET.
The SIP Switch is a Web application which allows you to use multiple SIP accounts on the same phone. This lets you use the call plans of different VoIP companies (using SIP) with one IP phone device. It does the third party SIP registration so you can receive all your calls on the sipswitch account. On dial out, you can set prefixes to make your outgoing calls with such or such provider.