Use for old grounds? I'm aware that coffee grounds can be great for composting, but living in a large city makes that more difficult than I'd prefer. 

With every cup of coffee comes a bunch of soggy grounds that I normally throw away shortly after. Are there any constructive uses for spent grounds, be it culinary, cleaning, or scent related?
They are very good as de-odourizers, we use them in the kitchen and sometimes in a small perforated plastic container in the footwell of the backseats in our car.

The fragrant smell lasts a long time also surprisingly.

Also it seems to be useful in fridges too.

That link lists the following:


Deodourize fridge
As a scouring agent
A cheap varnisher
Dye for paper
Promoting Hydrangea health
Ash absorber
Exfoliant
Cockroach trap
Fortifying plants
Compost


So the above is quite a good list of uses that could be applicable for your situation

I just found 34 uses here too, I have to say though that using ground coffee as a method for salting a path didn't work for me.

Additonal uses:


slug killer
mushroom grower
carrot and radish feed
worm attractor
cat deterrant (this didn't work for me)
play doh dirt
make a pin cushion
garbage disposal cleaner
drain cleaner
add weathering to wood
meat tenderizer
make energy bites
egg dyeing
coffee candle
make fossils
treasure stones
paint
flea bath
remove build up from hair
eye bag remover
deodorizing salt
salt scrub
face mask
path/road ice melter