A competition launched by Vodafone - the UK ISP that owns 45 percent of Verizon - caused red faces over the weekend as it was used to protest about the company's tax practices.
The company had promised to give away free phones to users who tweeted about something that made them smile using the hashtag #mademesmile.
But Vodafone hasn't been very popular in the UK over recent weeks. The company's been accused of having been let off a £6 billion tax bill by the authorities, although both Vodafone and HM Revenue and Customs deny this. It's a particularly sensitive issue at a time of massive government cuts.
Protest organization UK Uncut saw the competition as a good way of stepping up its activity against the company. "We've shut down dozens of their stores. Let's see if we can shut down their rubbish christmas promotion too! #mademesmile," it tweeted.
The tweets proceeded to flow in. "Shutting down Vodafone stores in dozens of towns across the country #mademesmile," read one. "The fact that Sir Philip Green is being called to account for Vodafone's £6 billion unpaid tax bill on their own homepage #mademesmile," read another.
And, compounding the disaster, Vodafone failed to moderate the tweets before posting them on its website and retweeting them far and wide.
"Within an hour #mademesmile was trending, and zipped to the top of Twitter’s trending topic list. Instead of the collection of warm, fuzzy feelings Vodafone had been hoping to have associated with their brand, visitors to the stream were treated to a barrage of tweets lambasting the company for dodging taxes," says UK Uncut.
"First we occupied their stores, then we occupied their hashtag. As one tweet put it – you’d have thought, with £6bn of our money, they could afford better advertising."