Progress Telerik Fiddler 

Progress Teleferik Fiddler performs HTTP and HTTPS debugging, managing the traffic between the web and your end system. The program can be used to perform such tasks as web session manipulation and security testing.

It comes wrapped in a decent looking interface, with nicely crafted menu icons, a simple left panel, and a large work area. It doesn't have any kind of skin themes, and the customization options are quite basic.

Progress Teleferik Fiddler can cope with various user activities, from web testing to HTTP and HTTPS traffic recording. You can use it to edit web sessions by simply setting a breakpoint to pause the processing of the session and permit alteration of the response.Perform security testing by decrypting HTTPS traffic and modifying web application requests.

It's also very useful when you need to debug traffic from PC, Mac, or Linux systems. You just have to ensure that the proper cookies, headers and cache directives are transferred between the client and server.

Overall, Progress Telerik Fiddler is a good choice for testing and diagnosing web applications and websites, though sometimes it misses some server requests, as well as a web filtering option, and the price seems to be too high.