I...could see these not going over real well.
The OSR Bonus Cards are a deck of cards designed for D&D or any retroclone, designed to be doled out to the players and allow them to gain access to small bonuses. I've seen some old school purists go so far as to say that giving players stuff like that actually means the games are no longer even RPGs at that point...that being said, I think they're kinda cool.
The cards are mapped to the standard playing card decks, with Jokers being wildcards. Clubs belong to Fighters, Diamonds to Thieves, Hearts to Clerics and Spades to Magic-Users.
Fighter benefits include an extra attack, an automatic hit or an automatic parry.
Thieves can score an auto success on a thieving skill roll, double damage on a backstab and various bonuses to thieving skill rolls.
Clerics can get an auto success on turning the undead, a free Detect Good/Evil or doubling the range and duration of a spell.
Magic Users can memorize a bonus spell, an auto success on an Intelligence check or a free Detect Magic.
They're a nice product for under $2 and not art intensive, so it won't be a strain to print them out...plus, being mapped to a standard deck of playing cards, you don't even need to print them if you don't want to. Just draw the cards and check the chart.
Great stuff from Small Niche Games once more, but I'm not a grognard.