>Sounds like the network is going down when the users are trying to log on first thing in the morning?

Often, could be laptop users with NICs set for 4 megabits per second. It was worse when the building next door was running at 4 megabits. Their field people would come in with their NICs set for 16 megabit, knock down their LAN, which would kill the NIC in our server that connects to their LAN, the driver for that NIC would say it detected the problem and disconnected, but it would eat up all of the CPU of the server so it had to be shutdown. Other problems are caused by loose cables and faile NICs. We have these IBM LAMs that cost about $80K that are supposed to provide protection from many of these errors, they don't work.
I would much rather work with 10BaseT. I see fewer problems on 10BaseT and the source of problems is easier to track down. 10Base2 and 10Base5 of course, have all sorts of termination and cabling issues because of the bus configuration.