INFR1 - The original Inferno, the one you know. Shadow0000 released a patch some time ago, look in the Inferno forum (not by the Inferno team). There is also a patch to make it SCP compatible, PM me if you need instructions. (Made by the Inferno team)
INF:SCP - A complete remake of INFR1, starting from the ground up. Uses the SCP engine and has many HTL ships. Yet to be released. (Work-In-Progress by the Inferno Team)
INF:A - Inferno Alliance. A campaign that shows what happened in the Sol system after the jump node collapsed. (Made by the Inferno team)
INFASA - Inferno Alliance Stand-Alone. And update to INFA making almost all of the ships HTL, and improving the campaign. (Work-In-Progress by the Inferno team)
INFA2 - Inferno Alliance 2. The sequel to Inferno: Alliance, will be released as a mod for INFASA. (Work-In-Progress by the Inferno team)
INFR2 - The sequel to INFR1, dropped in favor of INF:SCP (By the Inferno team)
S:AH - Sol: A History. Alternate campaign about Sol after the Lucifer disaster. Made by Blaise Russel. An amazing campaign, I have yet to play it as I can't get it to work. (Fan-Made)
And please don't spam smileys. One or two suffice.
Ha! Beat you to it, Snail! j/k