Ok, so this really isn't an idea for improving the fuel efficiency of anything, it's more along the lines of just not paying for the energy.
Imagine a hybrid gas/electric motorcycle. Are you imagining it? Ok, now imagine that its batteries are easily removable, easily concealed in a backpack, easily stowed under a desk at work.. and easily plugged in and recharged using your employer's electricity. Tada!
Ok, so.. problems: you're not going to be able to conceal or carry enough batteries to get you probably any more than a few miles down the road. That's why it's a hybrid – the gas engine will kick in and charge the batteries when needed. It's not perfect, and ethically it might be a bit sketchy, but it's one idea for coping with rising fuel costs.
I'm still waiting for the day when fuel is so expensive that it ends up being cheaper to just not go to work. I've gotta get some magic web-properties set up and bringing in income before then.