[chaetodon]

Lefthanders like me need an inverse Colemak to remain effective, given that many of the most used letters are on a QWERTY keyboard on my left hand (while with Colemak e.g. the E has moved to the right). Does an inverse Colemak exist?

[m_ram]

I don't think this exists. Using the keyboard layout analyzer [1], it looks like your perceived hand usage might not match up with actual usage. At least for typing out Alice's Adventures in Wonderland, Qwerty slightly favors the right hand (52% vs 48%). Colemak is only slightly worse for a lefty (56% vs 44%). Dvorak greatly favors the right hand (65% vs 35%).

[1] http://patorjk.com/keyboard-layout-analyzer/

[quink]

Left-handed Dvorak?