Who are these OS-tan? XP-tan and 98-tan are easy to recognize, but who are the others? This page only tagged 13 with no location.
All the girls are Windows OS-tan. From top to bottom, left to right, the characters/objects in that image are:


NT-san
Vistake (Windows Vista)
SE-tan (Windows 98SE)
Dreamcast lolly
1.0-tan
Inu-T (Windows NT Workstation)
DOSKitty
WinCE
3.11-tan
98-tan
SE's mechbox
95-tan
ME-tan
2k-tan (Windows 2000)
XP-tan
Homeko (Windows XP Home)
Moseko (Windows XP Media Center Edition)