Yes, avast U3 Edition is a discontinued product. It is still supported for those users who have a valid subscription but it's not possible to buy or renew the product anymore.
Vik:
I understand the logic of no longer selling the product, since U3 is now dead. But there are
still a
lot of U3 drives (and users!) out here that have the product and are willing to pay to extend their subscriptions to receive updates to their virus signature DBs. I urge Avast! to reconsider, and allow subscriptions to be extended.
(It will be at least another year before the flashdrive makers are finished hashing out the proposed replacement for U3, and in the meantime, a lot of us plan to stick with our old U3 drives.)
Or... is there a viable alternative that I can still install on my U3 drives and keep updated? Is there a "green" version of the Free or Pro products (e.g. doesn't use the registry, or "INI/key on Disk") ??