TransactionalMemory
From APIDesign
TransactionalMemory is an attempt to bring the power of databases to general purpose programming languages. wikipedia:Transactional Memory should be the ultimate source of information, however it seems that much better understanding of TransactionalMemory can be obtained by reading follwing practitioner's report. Joe Duffy's text is worth reading - it shows why weak TransactionalMemory cannot work. In the process of showing that it describes the gory details that remain unnoticed in the general overview at wikipedia:Transactional Memory.
I especially like the "these kinds of moments make me a believer in formal computer science" acknowledgement.
A more meta-level thought: Joe's text shows why it is important to properly document failures. Why it is important to describe roads that lead nowhere. As Jára Cimrman says: Should not we value the person who tried to blow a cigarette smoke into watter to find out that this process does not produce gold? Thanks Joe for showing us that (weak) TransactionalMemory can't work.