Generally speaking I only provide treasure where it makes sense and is realistic to the situation. I tend to use a literary approach to building treasure, though the treasure provided is something of value akin to answers already provided. I throw out things like coinage sparingly and only when its appropriate. Otherwise the things of value a being carries are dependent on what/where it is and what it was doing.
I do like intangible awards, like fame, recognition and similar social rewards. They provide for interesting adventures and give back to the players while snaring them into situations they might not otherwise become involved in.
Anything can be valuable. I've provided everything from various cloths to rare plants and earth as commodities of value. One good deed was even paid in glass, nearly one ton of it to be specific. Another, less beatific deed was rewarded with 50 bodies, cleaned, beheaded and skinned (by player request – it was an interesting run, let me say).
Functional items are a very normal provision. Alchemy items (potions, salves etc), herbs, helpful gadgets (technical, arcane and psychic), lifestyle items – all these and more make wonderful rewards and realistic treasure.
Which reminds me, I mentioned the literary method earlier. That's just coinage for taking a moment to describe, in words, what the treasures could be modeling off the real world. Just think for a moment about the functional things you keep on your person or in your conveyance and you'll begin, I hope, to see what I am talking about. In looking at my own self, I would name my phone, keys, coffee thermos (its early), clip to hold my phone, folding knife (very useful), and jacket. Where I in my car, this listed would easily double. My house? No idea but many factors higher. Using this tactic you can easily modify it to fit your game and generate treasure.
No that you may want all that treasure. It might belong to a group or family that will want it back and can recognize it. It could be cursed (unlikely), protected or locked to a person (better), haunted (you didn't kill him did you?), bad luck (ouch!) or punch your social trust in the face to give it a black eye when you sell it off or go around using the item of the guy they know well and is somehow dead now.