Canon has just announced the EL-1 Speedlite, a high-end on-or-off-camera flash that comes with a new rechargeable battery pack and a very low minimum power setting for creative uses.
This Epic Flash Dances in the Rain: Canon Speedlite EL-1 Review
The Canon Flagship Speedlite EL-1 Flash has an Updated Interface - Exibart Street
Canon EL-1 Flash Review by Ken Rockwell
This Epic Flash Dances in the Rain: Canon Speedlite EL-1 Review
Jeff Cable's Blog: Using the new Canon Speedlite EL-1 professional flash (Real world test)
REVIEW: Canon El-1 Speedlite Flash Review
Canon Announcements
Canon Speedlite EL-1 - Canon Flash - Canon Europe
Canon's new flagship EL-1 Speedlite flash comes with updated interface and new creative options: Digital Photography Review
Canon Speedlite EL-1: the first “red ring” flash by Jose Antunes - ProVideo Coalition
Canon Speedlite EL-5 External Flash