A role for pseudogenes: http://www.nature.com/nature/journal/v465/n7301/edsumm/e100624-02.html
A new role for expressed pseudogenes as ncRNA: regulation of mRNA stability of its homologous coding gene - http://www.ncbi.nlm.nih.gov/pubmed/15148580
"The number of pseudogenes present in the genomes of multicellular organisms is much higher than that present in the genomes of unicellular organisms. The number of human pseudogenes (~18,000) is close to that of the protein-coding genes (20,000 to 30,000). The noncoding genome, to which pseudogenes belong, may serve as a repository of at least a portion of the information underlying highly complex systems."
Pseudogene sequences are conserved, suggesting "pseudogene identity is preserved by selective pressure." According to the paper, "The existence of conserved processed pseudogenes that are transcribed irrespective of their position in the genome suggests that they are maintained to exert a specific role."
"Consistent with the notion that they exert biological functions, the expression of pseudogenes is a regulated process." Indeed, "various pseudogenes show a spatiotemporal expression pattern distinct from that of their coding counterparts," suggesting they are playing functional roles.
Source "Pseudogenes: Newly Discovered Players in Human Cancer," Science Signaling, 5 (242) (September 18, 2012)