Sometimes I have the need to RDP to a remote site but having to file a request with the IT dept. in order to get through the firewall can sometimes delay a quick 5 minute task into a 3 or 4 day task. Just not practical at all!
Thankfully, Ericom has come to the rescue with Ericom Access Now - a web-based "application" that lets you use their site as a gateway to the RDP connection you want. It's obviously not ideal, can slow the process down possibly, and adds a layer of complexity but at least it is an alternative that is (currently) free.
Check it out: http://app.ericomaccessnow.com/ *
* PS - I had this installed as a Chrome App on my browser but I am sure you can run it just from the website, although I have not tried this.