I did, and I have. A former colleague has a start-up digital magazine I showed him why Zoho was perfect for his three person company. I am his Zoho administrator as a side hobby which almost serves for me as a testing platform. Useful advice for small groups implementing Zoho is don't integrate/turn on everything at once. Adoption by the users in manageable chunks will be easier in the long run.
I have used CRM's and Salesforce Automation Tools from the beginning. I will skip Filemaker Pro, Act! and Goldmine and say SalesLogix was the first CRM I used and SalesForce.com was the first CRM I loved to use. The reason I appreciate Zoho so much is that SalesForce.com has become, for lack of a better term, too Fortune500. The tools and features are way beyond what Zoho offers, but cost of implementation and customization is way beyond most small business entities. The simplicity of Zoho and the low entry cost is what sold me.