Managing duplicate records is one of the hardest things to accomplish in CRM software. Just trying to determine what is a duplicate is hard enough and when you find a duplicate somehow you have to decide which fields need to be merged.
In ZOHO the process is almost automatic. I have spent so much time with this issue in the past that when I saw how ZOHO handled it I shed a little tear of joy.
Check it out. Go to any kind of record, Lead, Account, Contact, Vendor, whatever that you think is a dupe and click the Find and Merge Duplicate button.
You will go to a UI that allows you to narrow your dupe search. In this case I am using the email address and last name. I came up with 6 matches and four of them have the same email address.
I can merge three at a time so I check them and press the View Duplicates button. This is where the magic happens. I can choose which record is the master record and if the fields within each record are different I can choose which field will get merged. It works perfect. This is a huge feature that solves a huge problem and is so easy to use any temp admin staff person can do with minimal training. Not the case with any other CRM system I have used.
More information on the ZOHO Find and Merge process can be found here.