Netizens rushed to Twitter to react on Facebook, WhatsApp and Instagram outage, which lasted for several hours.
Owned by Facebook, the three services could not be accessed either via web or smartphone apps, reports BBC.
Twitter and Reddit were among several tech companies poking fun at their rivals.
The affected services had to take to Twitter themselves, as fun and serious messages burgeoned.
Major names from the world of entertainment, including Dolly Parton, have been getting in on the fun.
Others have been joking about seeing dormant Twitter accounts bursting into action again.
But Twitter may have started to smirk at its rivals prematurely, as many of its users started experiencing problems, with the Downdetector site showing a peak of outage reports at about 19:30 GMT.
Some, including whistle-blower Edward Snowden, have been using the outage to make a more serious point.
And others have been tweeting about how the outage is a good thing.
Meanwhile, the memes have been coming thick and fast.