Crisis of Infinite Episodes - DC Meets The Simpsons

Heaven knows that The Bartman was not the only reference that the Simpsons has made to the heroes and villains of the DC Universe. The first on my record was the cameo appearance of the Joker in season two's Old Money in 1991 hot off the heels of the Michael Keaton Batman movie. While I cannot promise that this review will be comprehensive, I will do my best. If I missed anyone, please post a comment and I will do my best to revise.

In 1999, the season 11 Halloween episode featured Stretch Dude and Clobber Girl. Even though there are a number of stretchy superheroes, but Stretch Dude's red costume seemed highly influenced by Plastic Man. 

In season 12, Comic Book Guy dressed as The Flash for a race in 2001's New Kids on the Bleech.

This classic Batman couch gag was reused in 2004 during the 15th season episode Simple Simpson which featured Homer and Bart as a Batman and Robin style crime fighting (pastry themed) duo: Pie Man and the Cupcake Kid.

The Simple Simpson episode also offered a quick satirical joke of a comic book titled Supergirl vs. the Glass Ceiling.

 
Other parody comic covers sprung up in 2007 on the 19th season episode Husbands and Knives beginning with a tribute to the Death of Superman related Funeral for a Friend found in Superman: The Man of Steel #20.

Silliness ensued with a Death of Aquaman cover,

Caveman Robin,

Black Robin,

and Born Again Robin.

Husbands and Knives also paid tribute to comic book writer Alan Moore (writer of Watchmen and V for Vendetta among others who lent his voice to the episode) with the comical cover for Watchmen Babies in V for Vacation.

In 2011, The Watchmen got some more love in the 23rd seasons, Treehouse of Horror XXII which had Homer dressed as Dr. Manhattan (thankfully with trunks).

 Husbands and Knives also used Wonder Woman as an inspiration for Marge to get fit,

 and allowed Daniel Clowes to show his utility belt illustration skills.

In 2008, the Season 20 Treehouse of Horror XIX included a Charlie Brown parody titled, Its the Grand Pumpkin Milhouse. One of the students at the school dance came adorned with a Superman costume, albeit a nerdy one.

In 2009's Homer the Whopper, a season 21 episode, Comic Book Guy's creation Everyman absorbed heroes powers from comics including Marvel's Iron Man and DC's Plastic Man.

Also in 2009, during Treehouse of Horror XX, Kearney came dressed as the Joker .

The Bob Next Door gave Batman some chalkboard time in 2010 during the season 21 episode. Bart wrote, "Batman is not 'nothing without his utility belt.'"

In 2011, a 60's style Penguin made an appearance on The Falcon and the D'ohman during a parody flashback of secret spy training.

 Later in the 23rd season, the Simpsons made a trip to the TV museum on The Ten-Per-Cent Solution where they had a pair of encounters with animated versions of the Batmobile...

 and a Fleischer-esque Superman statue that deflected a bullet.

On Holidays of Future Past, Bart was seen wearing a Guy Fawkes mask reminiscent of the one made famous in V for Vendetta during the Christmas card photo montage. Although this is the most recent reference on my radar, I am sure there will be more to come.

 Catwoman was a popular costume of the Treehouse of Horror XXIV special in 2013.

Also, the V for Vendetta Guy Fawkes mask returned.