Nothing says “it’s a party!” like balloons. But celebratory décor is just the beginning. Read on to find out how balloons have changed science, advanced warfare, and saved countless phones. (Some of these are fun DIY projects. Other should be left to the professionals, or the military, or nobody.)

1. ESPIONAGE

There were no airplanes during the Civil War, and no helicopters, or drones. But there were balloons, and Abraham Lincoln was ready to take advantage of them. These hot-air balloons were tethered to the ground and used to get an aerial view of the surrounding terrain, with one exception: on April 11, 1862, the balloon carrying General Fitz John Porter snapped its tether and drifted into the skies over Confederate territory. Porter kept his head, took meticulous notes of what he could see on the ground, and waited for the balloon to drift back into friendly skies, which, miraculously, it did.

2. CHILLING BEVERAGES

Got some extra balloons lying around? Fill them with water, tie them off, and freeze them. In a few hours, you’ll have a very festive ice bucket.

3. WATERPROOFING ELECTRONICS

Balloons are terrific for waterproofing, since they’re stretchy, snug, and waterproof. Simply hold open the neck of a balloon, drop in your phone, and seal it tightly. Voila! Dry phone.

4. DELIVERING MAIL

During the Siege of Paris in the 1870s, the city was surrounded and lost all means of contact with the outside world. With nothing left to lose, the city assembled a fleet of hot air balloons and sent them, loaded with information, passengers, and sometimes carrier pigeons, into the skies at night. These flights in the dark were surprisingly successful; between 1870 and 1871, the Parisians managed to deliver 2.5 million letters beyond enemy lines.

5. ABSTRACT ART

Give Pollock a run for his money with balloon painting. Spread a large sheet of white paper or canvas over a flat wall or ground surface (preferably outside, on pavement), fill a dozen small balloons with different colored paint, and let ‘er rip.

6. PEN GRIPS 

Nobody likes a slippery pen. To remedy the situation, cut the neck off a small balloon and stretch it over your pen (or chopstick, or drumstick, or licensed wizarding wand, whatever. We don’t judge).

7. GARDEN TIES

Cut a balloon into long strips and use them to tie your plants to stakes and supports. Unlike twist ties or zip ties, the balloon can stretch, thereby allowing your plants to continue growing freely.

8. WARFARE

Throughout history, armies have attempted to bombard their enemies with unmanned, uncontrolled balloons filled with explosives. For Japanese forces during World War II, this was largely unsuccessful. For the Austrians in 1849, it was disastrous: when the wind changed, 200 of their explosive-laden paper balloons came floating gently back and, well, exploded.

9. SUMMER LAWN GAMES

Water balloon fights are fun, but who wants to run around in the heat? Get your splash on the lazy way with balloon darts. Fill a bunch of water balloons, affix them to a board, stand back, and start throwing. You could also fill them with paint and make art this way, if you were so inclined.

10. DELIVERING THE INTERNET

One major internet company aims to send balloons into the stratosphere to beam network signals down to areas of little or no Internet coverage on Earth. Test flights in New Zealand, California, and Brazil showed promising results.

11. PAPIER-MÂCHÉ PROJECTS

If you’re feeling artsy, balloons make the perfect mold for rounded papier-mâché creations. The internet is full of tutorials for DIY lamp shades, bowls, party décor, and more.

12. SCIENCE!

The words “metal balloon” don’t really go together, but in the early 20th century we sure thought they did. The Explorer missions sent magnesium alloy hot air balloons—with passengers—into the skies, hoping to collect new information about Earth’s stratosphere. There were a few mishaps, and one explosion, but all the missions were a mild success.

13. FANCY-LOOKING DESSERTS

Everything looks posh in a chocolate cup. To make your own, blow up small balloons, then spray the rounded end with a non-stick cooking spray. Dip the tops in melted chocolate, then place on a parchment paper-lined baking sheet. Refrigerate for approximately 10 minutes—long enough for the chocolate to set—then carefully pop each balloon. (Before serving, just make sure none of your guests have a latex allergy.)

14. HEART SURGERY

Balloons are great because they start compact and can expand on command. This makes them a great asset for cardiologists, who thread them into arteries, then inflate them to compress plaque or make room for a stent. The classic type is the POBA—Plain Old Balloon Angioplasty, and yes, that is the technical term.

15. FOOLISH STUNTS

Remember the Balloon Boy hoax? Or any of the half-dozen guys who have tied themselves to a lot of balloons and hoped for the best? Something about balloons just captures our imagination and makes for an instant media circus—something to keep in mind the next time you’re feeling starved for attention.

As a bonus, here's one thing you should never, ever do with balloons:

16. SET THEM FREE

It’s 2016 and we can no longer pretend we don't know how bad free-floating balloons are for wildlife and the environment. Don’t do it.