I'm here once again. This time, bringing you Japanese dancers of Youtube and Nico Nico Douga. Now all the videos are from Youtube because I'm not sure how a Nico Nico Douga player works (in some cases you may need to sign up, I think). Many of the dancers are in fact from Nico Nico Douga, a Japanese video hosting site. There's a wide range of dances from idols' songs to K-pop songs to Vocaloid songs to other J-pop songs. I tried to appeal to everyone in my selection. I have to say that my personal favorites are Melotin + Miume's dance cover of Kyary's PONPONPON, S@PPOROID's cover of Berryz Koubou's Maji Bomber and Perfumen's cover of Perfume's Nee. Youtube page of BoutoKM has many dances from Nico Nico Douga. So I recommend everyone to check it out.
S@PPOROID - Berryz Koubou's Maji Bomber + T-ara's Bo peep Bo peep
S@PPOROID: Garana, YUK!e, Sando, Shiyubi, Danro
Melotin - Kyary Pamyu Pamyu's PONPONPON (feat. Miume)
Kozue Aikawa - Rukaruka★Night Fire + Riririri★Burning Night
ringring0118 - SKE48's Banzai Venus + ATA456P - KARA's GO GO SUMMER
Wonder3 - Perfume's Chocolate Disco + Perfumen - Perfume's Nee
L.A. - AKB48's Heavy Rotation + Beginner
Dancing Dolls - 2NE1's I AM THE BEST + SJJD's Mr. Taxi
317kayoko - Koda Kumi's KO-SO-KO-SO + Name Amuro feat. Yamapi's UNUSUAL
DANCEROID - Megu Megu☆Fire Endless Night + Bokaro's FirstKiss!
Wotano Musume.Meshitsukai - Kimura Yuki's LOVE&JOY + Ranka Lee's Seikan Hikou
Cuca - Tsukishima Kirari starring Kusumi Koharu's Chance! + C-ute's FOREVER LOVE (feat. mama)
source: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18