Lemons are hard core.
I like this article about all the ways you can use a lemon to clean, freshen up, make better, eat away, an otherwise difficult thing.
One of my favorite uses:
Keep insects out of the kitchenYou don’t need insecticides or ant traps to ant-proof your kitchen. Just give it the lemon treatment. First squirt some lemon juice on door thresholds and windowsills. Then squeeze lemon juice into any holes or cracks where the ants are getting in. Finally, scatter small slices of lemon peel around the outdoor entrance. The ants will get the message that they aren’t welcome. Lemons are also effective against roaches and fleas: Simply mix the juice of 4 lemons (along with the rinds) with 1/2 gallon (2 liters) water and wash your floors with it; then watch the fleas and roaches flee. They hate the smell.