For medium to large domain portfolio management select Domain Punch Professional
For large to huge domain portfolio management, powerful SQL based display and query support and extensibility select Watch My Domains ISP

The most advanced domain name management software (with the exception of Watch My Domains ISP). Includes all the features of Watch My Domains Professional, Domain Name Analyzer Professional and more. Supports monitoring the web sites associated with the domain (including ping and http home page check), email alerts when the status of a domain changes or if the server fails a ping test. You can also categorize domains into different groups for easy management.
Domain Punch Professional with database storage! This is mainly aimed at ISPs and large business users. Uses a Microsoft Access compatible database for storage and supports hundreds of thousands of domains. The data is also useable from Microsoft Access. Supports monitoring the web sites associated with the domain (including ping and http home page check), email alerts when the status of a domain changes or if the server fails a ping test. You can also categorize domains into different groups for easy management. Use powerful SQL queries to control display and lookups.
Almost all the features of Domain Punch Professional are available in Watch My Domains ISP also.