In this article, Ed Yong (http://flavors.me/edyong) describes the use of transcriptome sequencing for some extraordinarily large genomes:

"The red spotted newt (Notophthalmus viridescens) could sit in the palm of your hand, but its genome is ten times the size of yours – up to 10 billion base pairs. This daunting amount of DNA has kept this species off the radar of any genome sequencing projects, despite plummeting costs. It has also prevented newts and salamanders from becoming regular model organisms, despite their remarkable and medically-relevant ability to regenerate severed limbs and damaged organs."

SOURCE

http://www.the-scientist.com/?articles.view/articleNo/34650/title/Sequencing-the-Underdogs/