Here's my attempt at a summary of what needs to be done:
Basic enabling technologies, computers, software, networks, AI, biotechnology, nanotechnology.
Medicine: better treatments for viral diseases, cancer, aging.
Energy: anything that has prospects of actually replacing fossil fuels. Solar electric and algae-based biofuels currently looked like the most promising lines of development as I see it.
Space: anything that could shorten the time during which all our eggs are in one basket.
And I see three major ways in which individuals can contribute:
Personally work in one of the vital areas.
Make money and spend or donate some of it to support people who are doing such work.
Last but not least, this is a marathon not a sprint: take the long view and raise children who can do one or more of these.
I've been talking to a variety of people about this recently, and it was suggested that people (including myself) might benefit from a LessWrong discussion on the topic. I've been thinking about it on my own for a year, which took me through Neuroscience, Computer Science, and International Security Policy. I'm hoping and finding that through discussion, a much greater variety of options can be proposed and considered, and those with particular experience or observations can have others benefit from their knowledge. I've been very happy to find there are a number of people seriously working towards this already (still far fewer than we might need), and their deliberations and learning would be particularly valuable.
This is primarily about careers and other long term focused efforts (academic research and writing on the side, etc), not smaller incremental tools such as motivation and akrasia discussions. Where you should be applying your efforts, now how (much). Unless there's a lot of interest, it might also be good to otherwise avoid discussions on self-improvement in general and how to best realize these long term concerns, bringing those up elsewhere or in a seperate post.
A few initial thoughts: