Although our active security scanner has spidering features, our online Suite is lacking a dedicated web spider/crawler. The good news is that we already have an experimental spider, which we plan to release soon.
The Spider, although looking rather basic, is a very fast application mapping tool, which you can use to discover the URL structure of the applications you test. It works in two distinct ways. First, the spider tries to automatically follow links and submit forms. Second, it uses your browser wealth of information in order to go deeper into the application structure than any other tool.
We are still experimental with the tool but if you want to test it out yourself, just get in touch.