(Apologies for hijack)
HeyNow: When I moved in to my new house I didn't get a full night's sleep for about 2 months. Apparently one of the ladies in our neighborhood has big bins of food out to feed the feral cats and they have adopted us all. Between their shenanigans on the front porch at 3am, fighting and, well, performing other acts, and my cat's reaction to having them out there, I was a mess. Plus the smell on my porch was atrocious from the spraying and I was not enjoying the "presents" they left all over the side of the house.
I bought that ridiculously expensive cat repellant at the pet store, which seemed to lessen the problem, but there is no way I could afford to spread a box of that around the house and porch every other day. Plus, my cat hates the stuff and I hate putting out chemicals.
Enter coffee ground advice. I have no idea why, but most cats appear to hate the smell. I started emptying my french press leavings into the garden and all around the house (just dumped them in a different spot each day until I went all 'round, then started over). The cats still come around a fair amount but they don't hang out, scratch in the garden, or have parties in the middle of the night. I still wake up to the occasional fight but it is nothing compared to what happened when I first moved in. It also solved the problem of what to do with the grounds, as they are usually too wet for the trash can, but seriously mess with my 100 year old plumbing.
If you aren't a big coffee drinker, I even know of people who drop by local coffee shops and the shops are glad to give away bags (warning, you may have to bring your own bag or bucket) of grounds for "second use."