Keeping track of character equipment, weapons, armor, and loot is initially as simple as a list. Problem is a list only includes what it's author details. We end up with weapons and armor described on sheets apart from mundane gear, food and water (arrows too) reduced to hash marks on another area of character sheet and a vast accounting of every coin ever discovered by the character and all held together by an ever expanding backpack (if the player remembered to purchase one for the character). Throw in encumbrance to that book-keeping and a few things get missed.
I've long pondered using cards to solve this matter. A card can include every bit of info a game system requires (hopefully). A card is tangible, it's hard to argue one can haul about the 40 or so cards in a stack all in one little belt pouch and move about unencumbered. There are a few issues with cards however: they can get lost and you need a lot of them.
Cards can get lost. A player loses his character's stack of cards between sessions and they lose a lot of their precocious gear. Loss of equipment is a fate worse than death of a PC for many a player. One could argue a stack of cards does however encourage one to actually keep track of the precious goods. A little back up accounting can help but in the end cards can be lost.
The number of cards needed can be quite cumbersome if one really keeps track of what is needed.
A simple equipment list for a lowly fightign man could easily read:
Helmet, sword, shield, leather armor, boots, trousers, tunic, boots, water-skin, knife, tinder box, 50' of rope,30 g.p,15 s.p.,45cp and a weeks rations. That's 14 cards... or is it? Where's the character's loot carried, should those rations actually be 7 cards (collect yourself a days food and tell me it's not a noticeable amount of stuff), how many coins to a card?. With a card based system you have to wonder what's really worth keeping track of on a card.
With cards however we do get the visceral thrill of picking up your loot and digging through the pile of loot. Having cards to split up and argue over makes the treasure "more" and it also get's rid of the nebulous "party treasure' accounting I've often seen where a cloud of coins seems to magically follow a party around.There's no cheating involved when a player suspects the party member with twice as many cards as they have is pocketing an unfair portion of the loot.
Cards also allow for easy accounting of incomplete information. A card can describe an item without revealing it's true function with more detail than what a player actually writes on a sheet. Adm can even scribble in little codes for keeping track of magical treasures without requiring the player to scribble down an items serial no on an equipment list.
Just a little bit of pondering on the use of cards I felt like sharing. Cards have to be stored, legible, and durable too.