Hmm...the Barracuda solution may be a bit much for our purposes at the moment. Does MSE effectively block spam? I thought it was more malware/virus protection software.
www.untangle.com I'm using that product at more and more of my Small Biz clients.
Other hosted services...postini, appriver. mxlogic......to name a few.
As for the MSE recommendation, the OP stated that this is for a small business. MSE is free ONLY for home/home office users, not for businesses...same with other free AV software. So that would be against the licensing, and subject the company for violation and fines. Although it's a great antivirus, it's not an anti spam/phishing package.