Solution

Every index card describes either one module, or two modules with an operation. The title hints at Forget Us Not (commonly abbreviated as F.U.N.). Take each module's 3 digit code, and if there is an operation, perform it.

Clue(s):	Module(s):	Number:
Baseball position + obfuscated jacket decorations	Third Base + Complicated Buttons	229
Ritchey C260 84D	Superlogic	112
Kevin from battle royale game	The Cube	821
Arrays of pixels - First game in Sega franchise	Bitmaps - Sonic the Hedgehog	105
Preservation	Maintenance	521
Dodie Smith novel + advanced cables	101 Dalmatians + Complicated Wires	103
Despicable Me villians - Ratchet blocks	Vectors - Lombax Cubes	112
That light toggler + a joke in a manual	The Switch + Flavor Text	551
Boolean devices	Logic Gates	111
Piping system + line segment virtues	Plumbing + Chord Qualities	444
Medical radiation - visually impaired set of corridors	X-Ray - Blind Maze	214

To extract, organize the numbers so that there are 3 digits in each row, in order. Then read down the left column, down the middle, and then down the right one. This is clued at by the arrangement of the cards. Doing so gives us a message in A1Z26, without the spaces. The numbers at the bottom show how to divide digits.

2 18 15 11 5 14 2 21 20 20 15 14 19 2 15 13 2 1 14 4

This spells out BROKEN BUTTONS BOMB AND, the answer to which is:

BOOM