Before the cloud there was staff augmentation which remains and will likely continue to remain the most widely used form of AaaS.  By contracting consulting experts customers have been able to solve those tougher problems that don't fit into a cube, pivot table or BI report using their existing infrastructure. 

One technology evolution for staff augmentation that parallels the arrival of the cloud is the onset of web meeting software, fast internet and VPNs.  These technologies have opened up the potential for contractors to work remote.  Customers that trust this model and their contractors can potentially save on costs by engaging multiple skill sets from a larger consulting firm on a part-time basis.  The technology advancement allows the consulting firm to support multiple concurrent customers per resource without overhead incurred from putting people onsite.