Today, bitcoiners the world over will celebrate the anniversary of the most expensive pizzas in history.

Bought on 22nd May 2010 by Laszlo Hanyecz, the programmer paid a fellow Bitcoin Talk forum user 10,000 BTC for two Papa John’s pizzas. Back then – when the technology was just over a year old – that equated to roughly $25, but is $5.12m by today’s exchange rate.

At bitcoin’s all-time high last December, the pizzas would have been worth an eye-watering $11.47m, making them likely candidates for the most expensive pizzas of all time.

Now widely recognised as the first real-world transaction with bitcoin, May 22nd has come to celebrate 'Bitcoin Pizza Day', with cryptocurrency enthusiasts raising a slice to Hanyecz’s infamous hunger pangs that paved the way for early merchant adoption.

@BlueJayKay5 @CookiePounder Not on island at the moment, so I'll be celebrating #BitcoinPizzaDay with a big slice of Ham & Pineapple ;)

— Mrs P TheBitcoinWife (@TheBitcoinWife) April 30, 2014

"It wasn’t like bitcoins had any value back then, so the idea of trading them for a pizza was incredibly cool," Hanyecz told Nick Bilton in a recent interview with The New York Times. "No one knew it was going to get so big."

Yet, the picture today is vastly different. Worldwide, there are more than 70,000 merchants accepting the young currency, with block chain transactions now averaging over 57,000 per day.

In addition, data from coinmap.org indicates that more than 100 brick-and-mortar stores currently accept bitcoin for pizza – and this number is on the rise.

Retailers are getting in on the action, too. eGifter, the popular gift card platform is giving away extra points to customers purchasing Domino's, UNO and Papa John’s gift cards using either bitcoin, litecoin or dogecoin.

The company is also providing a 10,000-point prize in honour of the 10,000 BTC used in Hanyecz's transaction.

E-commerce platform provider snapCard is similarly commemorating Bitcoin Pizza Day by giving away 150 cheese pizzas for $0.99. At press time, the company was reporting an enthusiastic response, with roughly 30 orders placed in the first 10 minutes of the offer going live.

Closer to CoinDesk's headquarters, Takeaway.com lets UK customers choose from over 7,500 listed restaurants for home delivery, many of which may not even realise they are accepting the currency (albeit indirectly). After a quick postcode search for 'pizza' outlets, we decided to put the service to the test.

Surely enough, Papa John's – Hanyecz's brand of choice – came top.

A few clicks and a Blockchain web wallet workaround later (a drawback of using iOS) the pizzas were on their way.

Freshly-delivered Papa John's pizza at the CoinDesk office - Happy #BitcoinPizzaDay everyone! pic.twitter.com/CdEHOrujdr

— CoinDesk (@coindesk) May 22, 2014

How will you celebrate Bitcoin Pizza Day? Why not head to your local joint and raise a slice to Laszlo Hanyecz, whose late-night escapade changed bitcoin forever.

Who knows, maybe one day your pizzas could be worth $5.12m too.

Pizza image via Shutterstock