For the past few weeks now that is what I would hear every time I layered down to go to sleep.
Solution? Close the bathroom door so I couldn't hear it.
For a while it was driving me nuts to hear water leaking and know that it would be effecting my bill (and wasting resources) but I couldn't figure out what the root problem was. I could tell that it was coming from inside the tank of the toilet so I knew that it wasn't something that was going to cause any damage to anything, so I procrastinated fixing it since I'm not much of a plumber.
But on Monday it finally dug into it a bit and found that the price that seals of the water from going into the toilet bowl when you flush it (I later learned that it is called "the flapper") was letting water in.
Solution? I went to Home Depot and found a new flapper and replaced it in about 5 minutes.
Why was this a note worthy success for me?
1) I didn't have to pay anyone to come fix something that I didn't initially know how to fix.
2) I had been expecting to have to buy a new toilet since I could find what was leaking the first time I looked at it. That would have cost over $100 for the cheapest option but instead I fixed it for $5.81!!
3) The cheapest replacement flapper that would work on my toilet has a water saving feature that allows you to adjust how much water is used per flush, so now I'll get to see how low I can set it (while still being effective of course) and conserve more water.
Gotta love DIY projects!!