1. Look around your house.  Anything that you don't use, sell it.  EBay.com is a good place to start, and for free listings you can use eBid.net.  For larger items that you want to sell locally, try CraigsList.org.  Face it, we all have so many things that just sit there collecting dust that could bring you extra money.  For more information about how to sell things online, go to SurfsideMedia.com. 
2. Check into other ways to make money online - complete surveys or make your own money making Web sites.  There are some great drop shippers who will even completely build a site for you. 
3. Get a part time job as holiday help.  This time of year, many retailers hire extra workers.  This is a good way to make some short-term income.
4. If you live in an area where the temperatures are more temperate, have a garage or yard sale.  this is another good way to do some house cleaning, and make some extra cash.
5. Find more money in your budget.  Do you waste money buying things that you don't need, or could substitute?  For example, save by making your own coffee, carrying your lunch to work or school, or quitting smoking.  Keep a list of everything you spend over the next week, and decide what you can cut.  Many of us waste or overspend as much as $30 or more a day on average.  Why not take that $3 you spend on coffee each day and put it in a jar?  Then add $4 for cigarettes or beer, and $9 for lunch.  You have already saved $16 without even trying!

If you need more money, these are some great ways to get started on increasing your cash reserves.  Good luck!