Isn't there an easy one about clearing someone's debt? I forget his name, but it just involved a persuasion or bribe.
Also the Madesi's quest with the gems is hard as hell, I couldn't find the last flawless sapphire to save my life.
Why yes, there is. It's the stablehand I believe that needs his debt cleared.
Edit: Ignore number 1. That was a solitude thane quest, my bad. If you're still interested, the Riften court wizard asks you to go collect items she left lying around skyrim.