There are plenty of Super Sentai parodies out there, here are a few:
Disgaea: Hour of Darkness NijiRanger/Prism Rangers
The Prism Rangers are a troupe of gag characters which appear in the video games Disgaea: Hour of Darkness (2003), Disgaea 2: Cursed Memories, and Disgaea 3: Absence of Justice. Each of the members are named after the colors of the rainbow with the word Prism preceding it. Outside of the in-game battle, the Prism Rangers tend to be portrayed as weak, having been taken down in one shot or being unable to do the slightest bit of damage to their opponent.
Dragon Ball Z
Ginyū Tokusentai (Ginyu Force)
The Ginyu Force is a team of five mercenaries who are hired by Frieza.
Shiritsu Sentai Daitenjin (Municipal Force Daitenzin)
It is an adult-only, sentai dōjinshi by Rikudo Koshi, also the author of Excel Saga. Essentially, it is the basis of Excel Saga: Many of the characters designs that appeared in Excel Saga originated from the dōjinshi.
Negima!: Magister Negi
Magi Mahora Sentai Bakaranger
They were also featured in the television drama adaptation of Negima! titled MAGISTER NEGI MAGI: Mahou Sensei Negima!! As you may know 'Baka' means stupid.
Super Mario RPG: Legend of the Seven Stars
Kajiō Sentai Onoranger
In Japan, they are known as the Onoranger. In the US, the characters are known as the Axem Rangers. They appear in the video game Super Mario RPG: Legend of the 7 stars.
Tentai Senshi Sun Red (Astro Fighter Sun Red)
It is a manga created by Makoto Kubota that got an Anime adaptation produced by AIC A.S.T.A. that aired in 2008-2009.
UPDATED 5/11/10 5PM EST
Killer7 is a video game. The Handsome Men are an eight-man assassination group in killer7. Their stories focus on groups of fighters in brightly colored, form-fitting uniforms. There include Handsome Pink (female), Handsome Purple, Handsome Light Brown (female), Handsome Red, Handsome Blue, Handsome Dead, Handsome White Pearl, Handsome Gold and Handsome Black. Which seems to be 9, not 8.
Kanjani Eight Kanjani Sentai Eight Ranger
Since 2005, the Japanese musical group Kanjani Eight have created a series of performances at their concerts where they dress in different colored outfits and call themselves Kanjani Sentai Eight Ranger.
Bihada Sentai Sparanger
Toei has also parodied their work by using it in a series of shorts on various spas and onsen (hot springs) around Japan as the Bihada (Handsome Muscle Spring) Sentai Sparanger. This series has tokusatsu actors such as Takashi Hagino (Choukou Senshi Changerion and Kamen Rider Ouja of Kamen Rider Ryuki) as SpaRed, Kento Handa (Kamen Rider Faiz) as SpaBlue, Kengo Ohkuchi (played trapped subway worker Kazushi Mizuno in Kamen Rider 555) as SpaGreen, Masashi Mikami (BoukenBlue) as SpaYellow, and Kohei Murakami (Kamen Rider Kaixa) as SpaMurasaki ("purple" or "violet" in Japanese, a running joke would involve people referring to him as SpaPurple).