A much smaller presence than Outlook. Popular with large corporate users, although roughly half of its customers are businesses with fewer than 5,000 employees.
One copy of the Domino server software costs $1,435. Notes client software with instant messaging is $101 per copy, and Notes with collaboration features is $140.
Lotus Notes runs best when paired with Domino. Notes was created for collaboration and is the strongest product in this area. Comes with IM. More easily customized than Outlook. Hundreds of add-ons are available.
Domino has spam filtering. The Notes client software has "execution control lists," a feature that prevents viruses from running.
It's incredibly safe and secure. In its 15 years of existence, Notes has never had a major security attack. The CIA uses it.
A clunky, somewhat inelegant interface. It's not cheap, particularly since it really needs to be coupled with Domino. And its future is a little murky: IBM is planning to adopt a new messaging environment that will not be compatible with current Notes programming.