Before I went to work I downloaded Street Fighter X Mega Man
, the fan game turned official game that Capcom is using to kick off the 25th anniversary of the blue bomber. After work I checked it out, and I must say it's not too badly done. It's not perfect, as I did find a few flaws, but overall it's a pretty fun game. WARNING: the next couple of paragraphs contain spoilers about the bosses and their weapons you gain after defeating them.
For those not in the know, the game is basically an 8-bit Mega Man game where instead of Robot Masters and Dr. Wily, you have to take on 8-bit versions of characters from the Street Fighter franchise, and in true Mega Man fashion you gain their abilities after defeating the initial eight bosses. Afterwards you move on to what would normally be Dr. Wily's fortress, but instead you take on two classic Street Fighter bosses before the typical boss rematches. I'm not sure what's directly after that, but I know the final boss is M. Bison, and you can somehow unlock a secret fight against Akuma.
The game contains various Street Fighter and Mega Man references beyond the obvious. The music for each stage is an 8-bit remix of that Street Fighter character's original music, and even those had hints of Mega Man behind it. For instance, I believe the first few notes of Dhalsim's music was a reference to Snake Man's theme from Mega Man 3. If you defeat a boss with full energy (whether you used an E-Tank or not), you'll score a "Perfect". Finally, when you defeat a boss and gain their weapon, the weapon demo screen has Mega Man testing out the weapon on Dan, which reminds me of the Training Mode in Super Street Fighter IV where Dan's your...well, he's pretty much your training dummy.
Overall, if you're a fan of Mega Man or Street Fighter, I do recommend giving this game a shot. For the most part, it's not as difficult as past Mega Man games, but it's fun seeing the Street Fighter crew perform their signature moves...and yes, they do have Revenge Meters and Ultras, so be careful when their Revenge Meter gets too high. To check it out for yourself (it's a single executable file and a readme in a .zip file), head over to the Capcom Unity site