Battery Backup Power Solution

I am trying to design a power backup solution for a four workstation computer lab I administer. It is part of an eleven workstation domain running Win2k3 Server. Wall outlets are limited. Are there single Uninterruptable Power Supplies (UPS)out there with enough capacity to handle the battery backup power needs of ALL FOUR workstations. If so, what “workstation vs. UPS” specs do I need to look for? Any suggestions on brand name?