I have a few little things I do to make some side money - baby sitting, selling my book, and I have a massage therapy client I work with regularly. For a while I was just spending my earnings. Then I started saving them in our secondary checking account, so it wouldn't get spent by accident - I'm saving for an electric assist motor to put on my bike.
But I started thinking about something - we also have a credit card (0% interest) through that same bank, which we used to buy windows a few months ago. We have a plan to get it paid off before the 0% interest deal expires, but I thought it would be nice if we could pay it down a little sooner.
I asked at the bank if I could make payments on our credit card balance in person - they said "sure, as long as you have the account number!". So I made a commitment to deposit half of my side earnings in our account, and make payments on the credit card with the other half. Somehow it's much easier to just hand over the money to the clerk than to mail a separate check. Especially if the extra amount is only a few dollars, if I'm already at the bank, it's a breeze reducing my bill by $10 rather than the pain of writing an extra check, addressing another envelope, stamping it, and walking it out to the mailbox!
I know some people are disciplined enough to just set the extra payment money aside and add it to the regular payment, but I don't usually "do" the bills - Jake does. If I make these extra payments on my own, I don't have to pester him with depositing money into our "bills" account, reminding him to add that amount to our payment, etc.
It's also too easy to talk ourselves out of putting that extra payment in, if the money is already just sitting in our account. When I have the money in hand, and I make the decision to use that money to pay down our bill, it's great to be able to simply hand it over and have it go toward our bill.
This in person payment method can also work if you have a store credit card - at least, it used to. I worked at a jewelry store that allowed people to pay on their store card balance in person, and some department stores will still allow you to pay that way. If you're already in that area and dropping by the store isn't going to encourage you to spend more, why not take an extra $5 or $10 out of your pocket and make an extra payment on your bill? It makes a difference in how quickly you pay your bill down, and more importantly it makes you THINK about making the extra effort to reduce your debt.