Juliet from Los Angeles came upon this sign near the summit of a 12-km hike up Turrialba Volcano, in Costa Rica. “As I stared down into giant crater of the active volcano, dotted with sulfur pools, I realized the sign was right. Swimming in those pools probably wasn’t worth the expense.”

The dryly practical approach seems to be a popular one at tourist locations around the world — especially zoos, such as this one on Langkawi Island:

Meanwhile, this resort in the Bahamas adds its own whimsical twist:

related: You don’t need a cell phone to talk to God

Too busy to microwave your morning serving of saturated fat? No worries! If you’re a New Yorker, you can get your “special diet food” delivered right to your door. Or, um, your neighbors’ doors.

Our anonymous submitter can vouch for the note’s veracity. First of all, she says, the McDonalds is literally one block away from the apartment building. “But what’s worse,” she says, “is that the dude didn’t give his apartment number, so the delivery guy just started banging on random people’s doors and yelling ‘Scotty!’  in the hallway. At 7 AM!”

related: The time-tested “sausage, egg and cheese” diet

Remember: the laws of physics are not to be trifled with. Got that, Pigs Boson?

(Thanks to Luciel in the Bronx and Gina in Wisconsin for their submissions!)

related: Cross-country elevator action

Mothers truly skilled in the art of passive-aggression don’t need much to make their feelings known.

Just ask Rachel in Boston, who recently finished a three-semester master’s program a few months later than expected. “My mom was less than thrilled that my nine classmates finished on time while I struggled to edit my final paper,” Rachel says. “When I finally finished, we had a small graduation party, and she presented me with this gem of a cake.”

Meanwhile, writes our submitter in Madison, Wisconsin: “My mother has a bit of a ‘thing’ against any sort of carbonated beverage and constantly refers to diet soda as ‘the devil’s brew.’ I recently bought a little pack of the mini-cans of Diet Coke, and left one on the computer desk. After arriving home one evening, I found that my mother had kindly re-labeled one of my empty cans for me.”

In recognition of this particular skill, Amazon.com has apparently farmed out the writing of their suggested “PayPhrases” to stay-at-home Moms across the country…as Jessica in California noticed, on a double-take.

related: Is your blog kid-tested, Mom-approved?

Our anonymous submitter in Berkeley found this display in the bathroom she shares with her other roommates. “I hasten to add that the Imodium is not mine and the note is not directed at me,” she says. “Admittedly, the probable owner of said Imodium does need to get her shit together.”

So…perhaps the Vaseline was intended to help the the note-writing roommate metaphorically remove the stick up her ass?

related: (Untitled) Broken Glass

So, which of these warnings would most readily scare you into compliance?

Exhibit a) from an alley in York, U.K.

Exhibit b) from a sharehouse in Australia

or Exhibit c) spotted by Robert on a film shoot in Los Angeles?

related: Wishin’ and hopin’

“If you want respect,” barked the Daddy tree, “you gotta earn it. Show ‘some freakin’ acorns!”

“But Daaaaaaad,” whined the trembling young sapling. “I just…I just want to be beautiful!”

“What is this, a goddamn Shel Silverstein book? Quit your birching already.”

(As witnessed by Kevin in Arcata, California, and (below) by Taber in Richmond, Virginia.)

But as Michael in Seattle observed, at least one of those sad little trees wasn’t about to let his bully of a father have the last word.

related: The right to bear fruit

It all started, says Alex in Ottawa, when his roommate left on a note on his door, “chewing me out for not paying my share of the cable bill.” In response, Alex says, “I pointed out that he actually owed me more money for the hydro bill. Not being the kinda guy who takes well to being wrong, before paying me he decided to dock another $20 off what he owed — for random things like a burger he grilled for me six months ago.”

Eventually, Alex says, cheapskate roommate broke down and left him the 20 bucks…but not before adding a personal inscription. (Hover your mouse over the image if you’re having trouble deciphering the handwriting.)

Adds Alex: “That part about ‘my egocentric belief that I am free from wrong’ actually describes him to a T, I think,” Alex adds. “But what do I know? I’m just a ‘sleezy cheap fucker,’ off to spend my newfound drinking money…probably on a pitcher to share with all my pals.

related: “Communication needed”

extra credit: ["Defaced Presidents" pool on flickr]