U
- Ucluelet — XMetaL Developer 4.0 Service Pack 2
- Ulysses — Mandrake Linux 7.2
- UltraPenguin — Sun port of Linux 2.2 kernel for UltraSPARC
- Underdog — Sun PCI ATM
- Underground — WOWLinux 6.2
- Union Bay — XMetaL 4.6 (XMetaL Author, Developer and XMAX)
- Unisun — Sun Campus/SPARCStation 1
- Update 1 — Lycoris Desktop/LX Build 44
- Update 2 — Lycoris Desktop/LX Build 46
- Update 3 — Lycoris Desktop/LX Build 142
- Ural — ASP Linux 9
- Uzi — Apple Macintosh II
Read more about this topic: List Of Computer Technology Code Names