Internet based filing systems.....by a long shot.
We have developed our own in-house program, abilities similar to quick books online (view, edit and print all financial information from any computer on the net) but also includes some tools that are much the same as Xactimate. On top of that we input all our customer information including all paperwork scans (proposals, invoices, warranties, receipts for materials used, etc...) and even work photos into the system and any of our field techs or even our secretary can pull up all of the info with just the ability to access the internet.
We were even thinking of marketing our tools as roofing software (the closest comparison I can think of is like chronicle - a reference for you big stormers) but it seems to have so much more functionality as I just implimented a new proposal maker, inter-office memo, some features to send out reminder notices for warranty endings and service reminders, and with our in-house ability to program changes ourselves it has become such a useful tool it would be a shame to give it out. Besides that I am not too sure how xactimate keeps suppliers pricing up to date for various regions of the world so our pricing guides and estimate calculators are really only good for el paso.