Adobe Photoshop around v3/4/5 (newer versions may be as good or better, but I ha...

Adobe Photoshop around v3/4/5 (newer versions may be as good or better, but I haven’t used them)

Microsoft SQL Server 7 or later

NextStep

BitTorrent (more the protocol, but could also apply to any good implementation)

JetBrains software (pretty much any of it)

Think Pascal

ZFS

OS/firmware in Nokia “slab” phones from the late 90’s

StarCraft II, original Tetris, original SimCity (since all the cool kids are suggesting games)