Sleep deprivation is never a fun thing to deal with. Feeling groggy when going about your day can make it less enjoyable and productive. But being sleep deprived can also be a drain on your bank account. (See also: 5 Effective Sleep Tips You Haven't Tried.)[In Pictures: 10 Things You Should Always Buy in Bulk.]Here are six ways lack of sleep can cost you money.More Accident-ProneDriving sleep deprived can be as dangerous as driving drunk. Anywhere from 16 percent to 60 percent of car accidents involve a sleep-deprived driver, and 30 to 40 percent of all heavy truck accidents are caused by fatigue. Additionally, if you haven't gotten enough sleep, chances are you are going to be a bit clumsier than normal, resulting in a higher probability of having an accident doing routine tasks around the home or office.Increased Medical ExpensesPeople who don't get enough sleep are more likely to have health issues. People who don't get enough sleep are 15 percent more likely to have a stroke and 48 percent more likely to develop or pass away from heart disease. Additionally, people who sleep four hours or less each night have a 75 percent higher chance of being obese due to the fact that sleep deprivation can affect appetite hormones.Bad Financial Decision MakingIf you're tired, chances are you are more likely to make risky decisions. When you don't get enough sleep, you don't have as much dopamine in your system, which alters your decision-making skills. Sleep deprivation causes people to restrict their choices to decisions that promise bigger gains, which aren't always the best ways to accomplish positive results. In relation to your finances, this means that lack of sleep can alter the way you make financial decisions, causing you to make more risky gambles with your finances than you normally would.Sucking Out Success When you haven't gotten enough sleep, your brain doesn't function as efficiently and isn't able to remember things as well. It has been shown that employees who have insomnia cost employers $3,225 more than employees who get enough sleep. It has also been shown that students who don't get enough sleep the night before a test don't do as well on the test as students who do. The overall GPA of a sleep-deprived student versus a student who gets enough sleep is 2.84 as compared to 3.18.[In Pictures: Celebrities with the Biggest Money Problems.]Paying for ConvenienceWhen you are tired, you are less likely to take care of tasks on your own. Be it washing your car, making dinner, or cleaning your house, if you are tired you are more apt to look to other people to take care of those tasks for you. Paying for people to wash your car, buying fast food, or hiring a housekeeper can add up quickly.Caffeine CostsIf you are sleep deprived, you are more likely to shell out money for coffee or other forms of caffeine to help keep you alert throughout the day. If you buy espresso every day to help you stay awake due to sleep deprivation, you can end up spending upwards of $5,000 per year, or if you buy drip coffee everyday, you can end up spending close to $1,900 per year. You can save some money by figuring out which caffeinated drinks give the best bang for your buck. But ultimately, the best thing for your health and wallet is to get more rest.Ashley Jacobs is a college finance columnist for personal finance blog Wise Bread. Follow her latest tweets on @WiseBread.