The cause of his death remains unknown -- Averill announced Larsen's passing Sunday on his Facebook wall , writing that "It is with great pain and sadness that I tell you my son Mikey (Eyedea) has passed away ... At this time we kindly request your respect and our privacy as we process this devastating loss. We do, however, welcome your kind words, memories, and positive thoughts."

Known for his ferocious roller coaster flow and poetic gifts, the Rhymesayers-signed rapper emerged as one of the marquee artists of the underground boom of the late '90s and early 2000s. In recent years, he experimented with live jazz and rock fusion in the groups Face Candy and Carbon Carousel. But he returned to his hip-hop roots, recording last year's Abilities collaboration, "By the Throat," and performing on the Rock the Bells tour.

A battle-rap legend who notched victories at the rap competitions Scribble (1999) and the HBO-aired Blaze Battle (2000), Larsen recorded a trio of well-received albums with partner DJ Abilities, as well as a solo effort under the pseudonym Oliver Hart.

The indie-rap world was rocked over the weekend by the untimely death of 28-year old Michael "Eyedea" Larsen, who passed away in his sleep at his St. Paul, Minn., home.

The famiy has set up a Paypal account seeking donations to help defray the cost of funeral services. The news of Eyedea's passing has caused an outpouring of grief and eulogies from fans and friends. Below is a sampling of some of the reactions to the passing of one of the best to ever do it.

Minneapolis Star-Tribune: "He had one of the most rapid deliveries and fastest minds of any rapper in town, and now Micheal Larsen will be known for leaving us way too quickly."

Hip Hop DX: "While he may have been striving to understand others on a deeper level, he was always making music channeling this quest for comprehension of the human experience, a journey to understand joy. Eyedea’s name will be etched in the history books alongside many great figures in the game who will be missed. His rhymes remain cherished by his loyal fans, listeners who were able to relate to his stories or emotional verses in a way that transcends Hip Hop sub-genres or racial barriers. We lost an important voice."

MTV Newsroom: "Eyedea was a rapper, a poet, an artist, a label chief and -- most importantly -- a guy who wanted to push hip-hop to the outer reaches of its potential. He will be missed, but he'll be remembered for his slanted take on music."

City Pages: "Part of the Rhymesayers crew from its early days and a creative force to be reckoned with behind the mic, Eyedea painted beautiful and often abstract pictures with his lyrics, revealing the raw, serrated edges of emotion. He and his DJ, Abilities (a.k.a. Max Keltgen) were champions of their crafts and best friends since the age of 14."

Phat Friend (producer Blockhead): I remember being really taken back by how on point Eyedea was. He was much younger than all of us but yet was like a well oiled machine when it came to recording. That kind of skill and exactness is rare to see, especially back then in the days of lyrical miracle rappers who never rhymed the same verse the same way.

Beyond all the music stuff, Eyedea was a good dude. He was friendly and had boundless energy. I really enjoyed watching him mature as an artist and admired his drive and love of what he did. I wish I had gotten to see him more over the years... and see first hand, how he had grown up. My deepest condolences go out to his family and close friends."

Free Darko: "Those of you familiar with Eyedea know he was one of the most creative people alive."

-- Jeff Weiss

Photo: Eyedea. Credit: Eyedea MySpace