44. Bike messenge
40. Rent your apartment to tourists
If you rent once in a blue moon, list on Craigslist for free. If you want to make a habit of it, register at vrbo.com ($299 a year) and post an availability calendar. Another option if you're consistently out of town—list at citysonnet.com. CitySonnet offers rooms for $120 and up and private places for around $135 and up.
41. Substitute teach
In New York City, you need a bachelor's degree and no criminal history. Apply through the DOE website (schools.nyc.gov) starting in March; eligible candidates will be called in for an interview and writing test. Those who pass are added to the roster of substitutes to receive calls about gigs. Some are listed in advance, but most pop up either late the night before or around 5 or 6am the morning of. You can teach up to 40 days a year for $154.97 per day.
42. Sell your photos to stock agencies
Corbis and Getty Images are the biggest, but if you're not an established pro it can be hard to break in. Instead, try Shutterstock (submit.shutterstock.com), for which magazine editors and graphic designers pay a monthly fee to download royalty-free images. Each time a subscriber downloads one, you could get between 25 and $28.
43. Be a ChaCha guide
ChaCha (chacha.com), the service that responds to random questions from phone calls or texts, hires guides to text back answers from home. To apply, take a quick test on the website to determine your "guide role." We got info about becoming a guide via text, of course: "I was lucky enough to make Top Guide and now make 20 a text. Thanks for asking!" As a generalist or specialist, you can expect payments between 10 and 20 per completed task.
44. Bike messenge
There's a lot of turnover in the industry; so as long as you have wheels, you're golden. Most services pay a commission—ranging from 40 to 60 percent—based on the number of deliveries made, and a messenger who works three out of seven days might rake in $200 to $300 for the week. Cyclehawk (cyclehawk.com) has a good reputation; start there.
45. Be an extra
Despite the jokes, it's not such a bad thing to come straight out of Central Casting (875 Sixth Ave at 31st St; 646-205-8244, centralcasting.org). If you're nonunion, download a registration packet from the website and deliver it Tuesdays or Thursdays (11am for men, noon for women). Have a SAG or AFTRA affiliation? Go on Mondays, Wednesdays or Fridays at 10am. Currently, the most in-demand parts are prep-schoolers for Gossip Girl and faux cops and corpses for Law & Order and its spin-offs. "Every day is a deadline," explains Brad Kenny, manager of Central Casting. "At 4pm today, a show could call and say, 'We need ten doctors and four nurses for tomorrow—they have to fit these sizes and be this ethnicity,' and we rush to find those people." The pay ranges from minimum wage if you're nonunion up to $160 a day plus overtime if you're SAG. Also try: NYCastings (nycastings.com) and Back Stage's casting search engine (casting.backstage.com/jobseekerx).
46. Walk dogs
You've got two choices: You can look for a gig with any number of organized companies, or go it alone, just you and the dogs. Petaholics (646-723-1282, petaholics.com) is hiring poochophiles who are available between 11am and 3pm, and who have experience with animals (walking them, working at a shelter or vet and owning/caring for a pet of your own all count). Expect to bank $50 to $200 a week. NYC Dog Walkers (917-912-3968, nycdogwalkers.com) is also hiring—it prefers employees who've owned a dog. Those who go the indie route and post flyers in their neighborhood charge $15 to $30 an hour.
47. Do voiceovers
If you've watched Saturday morning cartoons like G.I. Joe, Teenage Mutant Ninja Turtles and Pokmon, you've no doubt heard Tom Wayland. The 37-year-old is a director-at-large for DuArt Film & Video and also freelances as a voice actor himself. "Compared to other acting gigs, like theater, voiceover work is the best bang for your buck," he says. "If you book a national union spot with residuals, you can make thousands and thousands of dollars over time." Wayland recommends signing with an agency like CESD Talent Agency (257 Park Ave South between 20th and 21st Sts; 212-477-1666, cesdtalent.com), which vets hopefuls by listening to their vocal demos. "[A demo] is your calling card in the voice world," says CESD agent Tom Celia. But he doesn't think you need to spend a fortune to have it professionally produced—editing together clips on your home computer will work just fine. And if you'd rather try to find work without an agent, create a profile for Voice123.com, which maintains a database of casting listings.
48. Paint apartments
You can post flyers until the cows come home, but your best bet is to befriend supers. Take care to wow your clients with your Michelangelo-like abilities (and your anal clean-up skills), so they'll recommend you to everyone in the building. Current Craiglist rates hover around $80 to $225 per room or $175 per day.
49. Start a "business"
Any hobby that could potentially make money can be considered a business for tax purposes. File a Schedule C and you can deduct expenses considered "ordinary or necessary," says CPA Neil Schloss of Castle Consulting. If your business is a band, that includes the cost of equipment, practice space, transportation to gigs, even concert tickets and CDs. You're allowed two years of loss with your business, so even if you don't sell any discs, you can still save on taxes.