Whether you own cat has had an accident, or the neighborhood Toms have decided to leave their calling card, that awful smell of cat urine is something that you don't want to linger. Save yourself from the olfactory assault with this trusted and true household product.

That's right, Vinegar to the rescue once again! This inexpensive miracle product is by far the best at tackling tough cat-related odors.
In a spray bottle combine 2 parts white vinegar and one part water and spray over the affected area and wipe with old rags. Sometime I even dump straight vinegar on the problem spot if it is still a problem.
The biggest mistake you can make, and many people do, is attempting to clean cat urine with bleach. This only exacerbates the problem, since the bleach brings out the strong ammonia scent in the urine.
In addition to tackling the smell, the use of vinegar also deters cats from returning to the same spot and spraying again. I have a veritable cat-colony in my backyard, so trust me on this one, it really works!
(Image: 1.

White Enamel Flatwa...
Best yet, mix of rubbing alcohol, hydrogen peroxide and a squirt of dishwasher detergent is amazing. Takes cat, dog or human pee stains out of anything!
I'm going to second Trishdom on this topic! Vinegar will remove the offensive scent for humans but it leaves the bigger problem of pets returning to the spot to repeat the offense.
Think of the larger picture and purchase a quality enzyme cleaner that will eliminate the odor for sensitive kitty noses. And while you're at the store, consider a pheromone spray to spritz around the spot to encourage them to view the area as a 'clean' spot!
get your local cat colony fixed. males spray.. which is a major part of the stink. also it is better to get the local cat colony all fixed so they don't reproduce. get information on your local TNR programs. (its a good deed!)
We put enzyme cleaner on cat urine spots so the cat doesn't pee there anymore, but I find that there's still a stale smell after using it... so when she targets washable things, I always add a half-cup of vinegar to the laundry and it works beautifully.
I had a fixed male repeatedly pee on my couch and bed... nearly ruined both of them. After trying a couple of expensive enzyme cleaners, vinegar, carpet cleaners, etc, I accidentally came across the best one yet. Mouthwash. I read on an unrelated post on AT I think, but some hospitals/nursing homes use it to clean bedpans. Anyway, after making sure to shampoo the bed and couch and suck the actual residue out, I soaked each down with mouthwash, let it soak for a day, then used the shampooer to extract as much of the mouthwash as possible, then let it air-dry. No more pee stink, and the couch and bed smell slightly minty, which just smells clean to me.
PETZYME! Works wonders, especially if followed with a spritz of Feliway to discourage repeat visits.
I have tried the following things:
nature's miracle
nature's miracle advanced
vinegar
cat deterrent sprays
and last but not least, I brought out the big guns. I got so sick of buying and trying new products, so I just did 50% bleach 50% water. So far so good and I have a very sensitive nose. I do think that 1/10th bleach to water will bring out the ammonia, but the pure stuff worked on the ikea foam couch I have. My cat peed on the foam so I wet it down, then I bleached, and then I vacuumed up with a wet vac.