  An estimate of the maximal informational content available to advanced
extraterrestrial or future (post)human civilizations is presented. It is shown
that the fundamental thermodynamical considerations may lead to a quantitative
estimate of the largest quantity of information to be processed by conceivable
computing devices. This issue is interesting from the point of view of physical
eschatology, as well as general futurological topics, like the degree of
confidence in long-term physical predictions or viability of the large-scale
simulations of complex systems.
