Suzumiya Haruhi-chan no Yuuutsu

Both are Chibi. Lucky Star is only Chibi in specific scenario's, though. They are also both about a group of teens going through comedic scenario's. 

Like Shingeki! Kyojin Chuugakkou, Suzumiya Haruhi-chan is a spin off / parody. Both are "chibi-like" comedy with the main characters from their series.  

Both are 3-D like animated series with very short episodes and are very funny. 

Created at the same time, has the same art style and to an extent the same humor. Made by the same studio, same characters, etc. There's no reason not to watch this if you like Churuya-san 

Both are spin-offs from original series and some main characters are chibi. 

Both use Chibi humor in huge amount Both has random humor both are really funny  

Both are series of shorts taking an (even more?) light-hearted view of their respective original series. (Of course, you probably want to be watching said original series if you're going to consider watching these; they might not make very much sense otherwise...) 

Funny short stories you will love 

Both are comedic counterpart series to their respective parent series and have short episodes (approx. 5 mins) consisting of non-stop gags based on a "toon"/"chibi" style of animation. Note that the Brotherhood series is a collection of parodies of significant events pulled from the main story while the Suzumiya series is a compilation of short side stories set apart from the main story. 

Another Spin-off centered in humor and chibi form of the characters of the principal show 

Both are about chibi characters with a hilarious plot and moments 

In a comic version, these spin off, including winks to the plot of the original series and lead us to our characters to situations that are not logical and not normally we would see. 

Both are parody OVAs of big franchises. Both are best watched after you finished the main series (Tsukihime-KagetsuTohya-MBs & Fate/SN-Fate/HA VNs and Suzumiya Haruhi no Yuutsu S1 & S2) 

They both have really short episodes, and both are really adorable! They are also spin-offs of comedy anime. 

As Haruhi is recommended from the main Lucky Star I feel that The Melancholy of Haruhi-chan Suzumiya - ONA should be recommended from the Lucky Star OVA. The latter is roughly 5 minutes per episode, but differs, and most important of all, it is absolutely HILARIOUS, in my opinion it is far superior to the second season. 

Both are spin-offs of their respective original series that poke fun at characters and where some characters are chibi-fied. 

Like short comedy stories about your favorite chars? Then you also like it. 

Both are spin-offs of their respective original series that poke fun at characters and where the characters are chibi-fied. 

Both are spin-offs of their respective original series that poke fun at characters and where the characters are chibi-fied. 

Spin-offs of main series, characters are in chibi forms 

both short funny series that will make you lol xD 

Both are cuts from the original series. They both generally do not have a huge storyline other than the original, however, both are extremely funny. It is recommended that you watch the actual Anime before watching the ONA. The Melancholy of Haruhi-chan Suzumiya may seem short, but it is quick and a fun watch. 

Both are small comical spin-offs of their respective series. 

My similarites is Haruhi Suzumiya is looks like Yuki Nakamura both are their attitude and being leader of the club. Haruhi is the founder of SOS Brigade while Yuri is the founder of SSS