Walt Disney World is known for its massive celebrations. From park birthdays and company anniversaries to “just because” promotions, there is always something exciting going on at Disney.

Many of these initiatives are fun if not overwhelmingly cool, such as 2013’s Limited Time Magic, which brought out rare characters and special parties for just a few days each. Every once in awhile, though, an event truly resonates with the public. Here’s a look at four of the biggest successes along with one spectacular failure and a celebration for the ages that introduced a bit of both.

1. HIT: Year of a Million Dreams

Begun on October 1, 2006, and extended through the end of 2008 by popular demand, the Year of a Million Dreams focused on making even the wildest Disney dreams come true. Teams of Cast Members known as the Dream Squad appeared at various spots around Walt Disney World (and Disneyland) throughout each day to hand out prizes to whoever happened to be there. More common prizes ranged from pins and special Mickey ears to all-day Fastpasses, admission to hard-ticket parties and VIP tours. Much more rare and coveted were multi-day vacations, cruises, DVC memberships and world tours to all of the Disney properties. But the absolute top prize for many people was something that no amount of money could buy—an overnight stay in the suite inside Cinderella’s Castle.

Part of what made the Year of a Million Dreams such a success was the sheer randomness of selection. The entire system was computerized, and a major prize winner might be “the person sitting in row 5, seat 4 on Mission: Space at precisely 3:07 p.m.” Minor prizes might go to “everyone who disembarks from Dumbo between 11:00 a.m. and 11:10 a.m.” Dream Squad teams were visible all over the parks, and the winners’ excitement was infectious. Non-winners on any particular day were often inspired to visit again in hopes of winning something the next day.

2. HIT: Epcot 25th Anniversary

Epcot’s 25th anniversary was the celebration that almost wasn’t. As the months leading up to the October 1, 2007, milestone ticked away, the official word from Disney was, well, no word at all. Eventually, leaked communication to a Disney fan site confirmed that the company was not planning any official observance. Appalled, some loyal Disney fans resolved to hold their own party, and Celebration 25 was born.

The Celebration 25 team was working on the schedule of fan-run events when they received word that some management changes had occurred and an official party would, in fact, take place. The official organizers gave Celebration 25 their full support, and what came from the partnership was a best-of-both-worlds spectacle that was extremely meaningful for everyone in attendance.

Upon arriving at Epcot that day, guests received an official celebratory guide map. On the front, it said, “The 21st century began October 1, 1982.” Inside was a replica of the original opening day map, along with a listing of the day’s Disney-sponsored special events. With the guide map, guests also received a special 25th anniversary button.

An excellent rededication ceremony took place at 10:01 a.m., featuring speeches by top-ranked management and even Imagineer and Disney Legend Marty Sklar. A particularly nice touch was the rededication of the Fountain of Nations. On October 1, 1982, representatives from all the countries of the World Showcase had dedicated the fountain by pouring in water from their respective nations. On October 1, 2007, they repeated the water pouring ritual (though due to the last-minute nature of the celebration, I imagine this time around it was symbolic water acquired backstage).

Those who wanted to hear more could attend a special talk by Marty Sklar in the Circle of Life theater at one of three times throughout the day. Although the theater was packed, we had little trouble getting seats at the time of our choice. Marty presented concept art, videos and innumerable personal anecdotes that earned him a well-deserved standing ovation.

A particularly nice touch was the Epcot 25th Anniversary Gallery. Open for several months, the gallery was tucked into a back corner of Innoventions West. It featured some truly impressive artifacts from closed Epcot attractions, and was a nice retrospective for both long-time attendees and new visitors. Limited edition T-shirts and pins were also available, though they sold out very early in the day.

Combined with the fan-sponsored Celebration 25 events, Epcot’s 25th anniversary turned out to be one of Disney’s biggest successes. Because it was pulled together at the last minute, and was only a day rather than a year, it felt intimate and special. In the days of constant marketing, it was nice to attend something small and largely unpromoted.

3. HIT: Give a Day, Get a Disney Day

Image: Disney

For 2010, Disney decided to promote volunteerism while encouraging people to visit its parks through the Give a Day, Get a Disney Day program. The idea was simple—by signing up for and completing a single day of volunteer service, you were eligible for a one-day ticket to Disneyland or Walt Disney World. With a mind-boggling array of organizations and positions from which to choose, and opportunities available across the U.S., Canada and Puerto Rico, it was easy for families to find something to do.

Every person who participated got a free ticket for the day of their choice, making it easy for entire families to visit a park of their choice without paying for anyone’s admission. In addition, the free tickets were fully upgradable, even to annual passes, simply by paying the price difference between a one-day admission and the chosen upgrade.

Disney pledged to give away 1 million tickets, and the campaign was so popular that they hit that goal in March 2010. Vouchers could be redeemed through December 15. Although it might seem slightly mercenary to complete volunteer service in exchange for a theme park ticket, the program was a win-win for everyone. Disney got more people into the parks, presumably spending money on food and souvenirs. People who were unable to afford a Disney ticket were able to make a work trade arrangement. Charity organizations got much needed help, and ultimately the recipients of the charities’ goods and services benefited from the work.