I would like to nominate two quest rewards as the most useless of all the rewards available in the game:

1) Kyne 's Token
After demonstrating that you can kill any animal Skyrim can throw at you, you get an amulet that reduces damage from animal attacks. Why? You have already shown you can kill them, which means they didn't kill you. So now I can be sure they can't kill me? Duh.
It would have been nice to have a token that gives you a permanent Voice of the Sky effect. You beat the snot out of Kyne's creations, maybe they should show you some respect from now on!

2) Prowler's Profit
As many dungeons as you have to go through to get this, and considering the fact that you have to buy the most expensive house in the game to complete the quest, by the time you get it you are already rich beyond reason. By the time I complete this quest I don't even bother looting the bloody jewels anymore. Who needs them when I am rolling in coin?

Uhh... Some hunter near Falkreath gave me a pathetic dagger that belonged to his recently slain friend.

So, you want even MORE "epic" rewards and artifacts from Skyrim? I think it should have more rewards like these you described, and less money rewards and superpowered items.

Can you please give me a list of "superpowered" items in Skyrim? Because Skyrim no longer has chameleon, and the only "superpowered" items would be DBGloves and Ebony Mail's permanent flame cloak effect coupled with invisibility, other than that they all blow.

That's a cool dagger, man. Imo, one of the best.