Suki na Mono wa Suki Dakara Shou ga Nai!!

one of the the characters has to dress up as a girl, they go to an all boy school, and they all have the same hair color 

They're both shounen-ai school-based and humorous. The general mood is similar too. 

Both are sweet boy's love stories. 

To me, Sukisho is quite similar to Junjou in a few ways. Very sweet plot. Contains yaoi. :) 

Sukisho is similar to D.N.Angel because they both have the 'alter ego' plot.  

Gravitation and Sukisho develop the growing attraction between two male characters with plenty of comedy thrown into the mix. Both can be rather random and off the wall but have a darker undertone that becomes prevalent in the later episodes. If you like shounen-ai that actually delivers a solid story and has vibrant character designs, both series are a very entertaining take on boys' love.  

Different in many ways, but similar themes with being experiment subjects and both with interesting plot twists 

Romance, Comedy, the odd Ecchi moments, although in Sukisho it is "male ecchi" and in Chobits it is "female ecchi", Drama is amplified a lot during the second halves of the series 1 or more characters in both have alternate forms / personalities in order to help them find their love. both involve "psychological experiments" in some shape or form 

Both have relatively similar comedy styles (ridiculous humor), with an entirely male cast. While Sukisho is a shounen ai, Binan Koukou Chikyuu Bouei-bu has some gay suggestions (especially in episode 3). 

No.6 and Sukisho both deal with two main male characters (who seemingly develop crushes on one another, although it's a bit more obvious in Sukisho). Their plots are both actually really unique and complex and they both deal with being stuck in a facility, or, in No.6's case, a really strict, futuristic city that is not what it seems. The main characters aren't all that different from one another, and they all have deep and dark pasts. Sora (from Sukisho) and Rat (from No.6) are both the passive-aggressive characters in the animes who have that secret soft side. No 6. and Sukisho are both great underrated animes that I would recommend to anybody.  read more 

Both Sukisho (Suki na Mono wa Suki Dakara Shou ga Nai!) and Golden Time deal with memory loss and dual personalities as a result of a traumatic accident and both are romances. However, Sukisho is BL and Golden Time is straight. 

- they both contain shounen ai - the character have more hidden in their past then we know of only suki na mono wa suki dakara shou ga nai is darker than junjou - they both (live) toghether with their love interest.(like misaki and usagi) - they both contain drama and comedy aspects 

also a tormented back story. easy to see, and more evolved relationship. alike in sex scenes (there are, but only as fan service). 

Both an all boy school 

Both are 12 episodes mystery/romance anime based on otome games. In both, the conclusion of what the hell is going on arrives at later episodes. The main character is very oblivious as to what happens around him/her. His/hers love interest(s) are discovered to hold dangerous secrets. Both endings are very dramatic and have characters in deadly situations. The story and characters are better in Sukisho though, in my opinion. 

Both male leads can't remember another boy from their past. Also, both are BL, and made from erogies(hentai games). 

Sukisho and Be-Boy are shounen-ai productions that play on the mains misunderstanding each other. Sukisho is mostly a comedy but has a very dark backdrop while Be-Boy is cute and mostly harmless. In both the relationship between the boys is tested and it is likely that these anime share the same fanbase.  

they are both boyXboy...but this is yaoi and shonen ai in some sections of the anime...but anyways if you like boy x boy and the love affairs between one male mate to the other ...then eventually patch things up and be together at the end its the anime for you!!!! 

while one show is a historical samurai anime and the other a shounen ai school romance there are great similarities in the structure. both shows are written by Mamiko Ikeda, and i assume that's where the similarities come from: both shows are 12 episode light shows in which the dark story kicks in around episode 9. they revolve around a romantic couple that use to tease each other. it is told from the masculine point of view while the feminine, although happy and charming at first, holds dark deadly secrets. there are two male guardians with an intimate relationship that guide the couple but also watch over them and know more about their destiny than they let on. the story is used more as a tool to put the couple through trust and honesty challenges and dramatic situations rather than try to deal realistically with its subjects. both shows have predominantly male cast. read more