From Npust software:
Npust email list manager is a high performance mailing list management application that will allow you to manage your email lists faster and easier than ever before. Npust email list manager is freeware for personal use. Commercial use is not authorized without agreement. Try Npust email list manager, our organizational utility for Internet marketers. It will allow you to: Combine several lists into one file. Split large lists into several files. Clean duplicate addresses. Remove addresses based on domain or keyword. Extract a user specified sample of email addresses from a master maillist. Sort and remove duplicates from user specified files. Randomize the email addresses in user specified files.