Ultima III Gold is an enhanced and bugfixed of Ultima III for the Commodore 64. The original port from Apple II suffers from a heap of technical problems and has some of the sloppiest code I've ever seen.

Supports 1541, 1570, 1571, 1581, CMD FD, CMD HD.
Fits on a single disk side
Keyboard remapping
Movement keys are now sane on non-english keyboards.
Unlimited Magic
Unlimited Food
Unlimited Torches
Unlimited Keys
Unlimited Gems
Press T to teleport (X/Y coord 0-63)
Press (B) to mount (H)orse or board (S)hip
Press (X) to exit combat
Yell "AMBROSIA" to travel to/from Ambrosia
Code optimizations
The tile plotting routine has been rewritten which speeds up the game significantly.
Revamped save system
Removed redundant sosaria save for performance reasons.
Sosaria map is cached in ram when entering townes.
Only saves to disk when asked to - no automatic save when the party dies.
Buy more than one dagger at a time
Select default character
Press 1-4 to select a default character for actions. Press 0 to revert to the games default behavious where it asks.
Ask on location exit
The game asks before it throws you out to the main map.
Delete key now works when entering player name.