The amazingly talented Damien Fate, who has been keenly developing his next-generation tiny avatars Loco Pocos, has launched two awesomely cool videos showing off flexible sculpties on his latest batch of Loco Pocos avatars!
Flexible sculpties (or FlexiSculpties) are not part of LL’s plans to be integrated in SL soon. Still, Qarl Linden has been looking into the amazing work done by Zwagoth Klaar, Kristie Young, and Uchi Desmoulins, who have created a set of patches to allow this to happen. The specially crafted viewer has been around for five months now, but you ought to vote on the JIRA if you wish it to be implemented.
For now, you can always try out an experimental Imprudence version which fully supports them.
(There is also a YouTube version available)