I'm not sure if anyone's thought of this, but if you're on Pinterest (a social bookmarking website where you can have followers that see what you pin, you're pretty much sharing your favorite things by pinning them, as well as simply saving them so you can remember them yourself. You can in turn follow other people that are pinning things that are interesting to you, and find things you like that way.
This could be used to our advantage...) and you've read (or want to read) a fellow HWers' book, you could pin it, saying how interesting it sounds and maybe having some of the description on the "back cover" to go with the pin. Then anyone browsing the homepage might see it and repin it themselves, so that their 10,000,000, followers (ok, maybe not that many, but you get the idea) will also see it, and repin it if they like it, and so on.
To get an idea of what a pin like that would look like, here's the one I did so far: http://pinterest.com/pin/122441683589239612/
One word of warning about Pinterest: people do pin inappropriate stuff on there, so I recommend that you don't follow other people's boards unless they are labeled specifically something you're interested in, for example, someone like myself likes photos, but I need to watch for boards labeled "wildlife photos" etc.
Lastly, if you're not on Pinterest, but you want to join, I or someone else on HW that's on there can invite you.
I thought you'd like that one. 
You do use pinterest a lot. What is the Starsailer universe?
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