Webhookr is meant to be able to get live feedback of HTTP requests. If someone or something sends a request to a Webhookr you have open, then you'll hear and see about it.
curl http://webhookr.com/38a4H4 -d "data1=something" -d ""
You will see the request displayed on the first page you opened the moment it comes in, accompanied by a sound effect.
Webhookr support arbitrary sub-paths, so if you have multiple requests coming to one webhook, you can differentiate between them. Just add /whatever/whatever/ to the end of the webhookr URL and when the request comes in, you'll see the path in the request title, to the right.
The sound effect for each callback is customizable. Just make the first part of the sub-path the name of the sound.