Companies that cannot afford to upgrade to Windows 2000/2003 or that have servers that won't run Windows 2000 and above. Sort of like those who still run machines that are 5 to 10 years old and cannot afford to buy new ones.

When I worked at the small business that delt with hospitals, the server used for storing the main database was NT 4.0 Server, they couldn't afford to upgrade all the hospitals to Windows 2000 Server because they are a small business with a limited budget. So limited in fact that they told me if they didn't get enough new hospitals that they may not afford to keep me or others that worked for the company. The software we wrote was like a POS system but kept track of surgical trays and the surgical instruments and how they got washed. Many other companies were doing this and it was very competitive.