Small businesses represent two challenges for
CRM software: CRM software tends to be expensive to purchase and CRM software also tends to be expensive to maintain.
In a larger organization, there is usually more funding for the initial purchase and there is usually funding to keep dedicated administrators on staff for the software.
The first issue can be resolved with some of the really excellent
open source CRM software packages available today, such as opentaps, Tunesta, Compiere, vtiger, XRMS, SugarCRM, Ohioedge, openCRX, and EGS.
This does not resolve the second issue. Any CRM solution is going to require time and effort to maintain. One possible solution to that is to rent space on a hosted CRM solution provided by an ASP (Application Software Provider).
Tunesta offers a service of that nature, which they call "On Demand." Compiere has several partners which offer their software in an ASP business model. Siteground is a hosting company which offers pre-build vtiger implementations as part of their ASP offering. Sugar offers SugarCRM in an ASP model called "Sugar On-Demand."
Basically, the new model is that you do not need to own a software package to make use of it. This model is particularly attractive to small businesses, who do not usually have the budgets to support large IT staffs.