Yes, you can run an ISP on Mac OS X Server. I am currently doing everything an ISP does EXCEPT account management and billing. If you need that there are products out there that will work with Mac's. Mac OS X Server 2.0 (according to the apple's pages) will include all the stuff you need except RADIUS for dialup authentication and except for account management. You can do RADIUS (I got the cistron RADIUS server compiled on my X machine, there is also a Mac OS X Java based RADIUS server that was announced the other day.) Mac OS X Server includes SMTP/IMAP/POP services, so you don't need to buy communigate (I would recommend communigate though, it's a great email server, but if you are only going to serve a few users, not really needed IMHO) If you want the fully automated account management/billing/creating/etc. You'll need to research a bit more and it's all about your hassle. When I have a new user, the user has to be put in the email server, a web user must be created for FTP access, there site directory must be created, etc. It's not automated at all, but I don't have to do it very often. There are utils out there to automate this whole process.