Fantasy Flight Games with both their Star Wars RPG and L5R have made systems where you use specialty dice to determine results. The idea in both games is the dice give you more than just numbers to add up, but several meaningful things to the game.
FATE also has specialty dice - fudge dice in specific - where you roll D6s that have 2 blank sides, 2 plus sides, and 2 minus sides. The idea being to get a result from -4 to +4 on every check before applying skills, aspects, and other bonuses.
My question to you today is do you like these dice? A lot of people seem to take issue with them, and they definitely add to the cost of what can be an already expensive game system. But even if expensive do they add to the game?
My answer is split. While I like what fudge dice are trying to do, this is just numbers in another way. There's no reason you couldn't use regular dice and just adjust how the ladder is so that a 4-8 result was "bad" a 12-16 was "neutral" and a 20-24 was "good" and more or less have the same ladder. Or just use other dice to get a similar range.
However, when it comes to Fantasy Flight Games, while I don't like that a set of Star Wars dice is not enough for an experienced character to make a hard check, I do find that the Success/Advantage/Triumph/Failure/Threat/Despair potential of the dice does add a lot to the game and how it plays out. In the same way L5R's Success/Strife/Opportunity/Explosive Success adds more to the game than just dice.
Essentially, while the cost may be prohibitive, if I remove that factor from the equation I really like what FFG has done with the dice. If I put it back in, it just comes down to whether or not the cost is worth for what it adds. And with that, I bought the Star Wars die roller for $5 when it came out years ago, and that means I don't need to buy dice for any FFG Star Wars game they've released, which is a hell of a value. As for L5R? Buying a couple sets means I have enough dice for all the players at my table - though it means sharing somewhat - and that cost is worth it to me for the game world I love.
What about you? Do you like them? Is it worth it in some situations?