I had never heard of this until a recent comment by Tamas Simon on a teleread post
, but OpenBerg Lector
is an e-book reader extension to FireFox that supports .epub. Adobe Digital Editions can display ePub in a browser, but it isn't currently cross-platform like FireFox. So far I have had mixed success (i.e. mostly failures) using this, but I am not convinced that all the problems are with OpenBerg. At a minimum this provides another target for compatibility testing.