This is one of those neat accessories that you probably never realised that you needed until it happens to come your way. However well-organised your character sheet might be, however encyclopaedic your knowledge of the weapon stats in your chosen game system might be... there always comes that moment when a number or a property of your weapon eludes you (and that moment almost invariably occurs when some slavering adversary is bearing down on you...).
The idea is simple: give each weapon a separate index card with all pertinent details on it, then pluck out the relevant card when you wish to use that weapon, and have all the information you need just when you want it. Some of us have been doing it for years with painstaking scrawls on 5x3 cards or the like... but it's much nicer with a considered layout and a pretty picture or two.
Their usefulness is not just limited to combat. If you are the GM, it saves time when rooting through treasure hoard or loot, or when the characters decide to visit Ye Olde Weapons Shoppe to spend their hard-earned gold. I even once, many years ago, had a DM who insisted everyone had a small containing a card for each item they were carrying... and then sometimes would grab it and rummage through, leaving you wondering if a pickpocket was relieving you of something! That's probably going a bit far, but there certainly are a myriad of uses to which such cards can be put.
It is all very nicely presented, and makes good use of PDF 'layers' technology to let you decide just what you want on each card. The variables are outline (card border), weapon picture, two separate areas of description and the background - available as a red splodge (blood splatter), a grey one or absent. The two descriptive areas are interesting, one of these has the 'stat block' as appropriate for Pathfinder or similar rulesets, the other is freeform, so you can write comments or a description of the individual weapon (or indeed anything else!) there. If you are not using a Pathfinder-compatible ruleset, you can turn off that part and write in whatever statistical details are appropriate for the game system you are playing.
There's a good range of both common and more exotic weapons: whatever you fight with, there's probably something at least similar in there (or switch off the weapon image - you could always stick a picture of your chosen implement if you really want to)... and of course, as this is a PDF not a deck of cards, you can print as many as you want. For the full effect, there are card backs - two designs to choose from - and it's a relatively simple matter to either print both sides if using a good card stock, or just print out on paper and glue onto card if printing on card is a bit too much for your printer.
One of those handy accessories that can enhance a game, perhaps a bit fiddly but if you are happy handling cards - and they are the right size to use commercially-available card envelopes such as trading card players use - you might well wonder how you coped before you got your hands on these. Visually, it makes your weapons that bit more 'real' than a line of text on your character sheet too, and giving a weapon to someone else becomes a simple matter of handing the card over.