From LivePIM Software:
LN Duplicates Cleaner lets you remove duplicate information in Lotus Notes Contacts and Calendar quickly and smartly.
LN Duplicates Cleaner provides a wizard user interface lets you check and remove duplicate information step by step. You may delete the duplicate records you selected or delete all the duplicate records with a few simple clicks.
LN Duplicates Cleaner also provides options let you customize your own duplicate checking rules which you may remove duplicates as you wish.