Potions
Besides drinking rice wine and watching TV, Urd also spends a large amount of her time working with potions. And despite the various misadventures caused by many of her occult creations, she seems to be quite an expert at it. In fact, many of the magical mishaps usually are not directly caused by Urd but rather the intervention of a third party (whether it be Skuld, Marller, or otherwise) or some other goofy occurence which so characterizes the Oh My Goddess! universe.
Urd's interest in potions shows a more meticulous, almost academic side of Urd that is not shown frequently in the series. Not only does she keep careful tabs on all of her ingredients but she appears to count them at least once daily. This has allowed for her to remedy several mistakes on the parts of others who felt a need to swipe various materials from her stock.
And now to look at more specific examples. Some of Urd's creations have proven not only to be functional but.. *gasp*... useful!
Potions