It is a site that a ton of GC's are signed up with. They can put a project up, and according to the job codes that you have entered (codes that define the type of work you do) you will receive an e-mail notifying you of the RFB.
It is also an online plan room. You can view plans and even specify a location on the plans that you have questions about and e-mail that question to the engineer, the GC or whoever else might be able to answer it. You also have the ability to put the plans on a thumb drive and have them printed out at a print shop.
My step dad uses it at Kiewit. Thats how I found out about it. SEMA and Granite are a few of the big ones that use it also.
I am not trying to sell anything here, just was wondering if anyone else uses it?
Check it out at isqft.com
Pretty sure that I am going to sign up, I have had 16 RFB's for the state of Colorado in the last week.