My search for more expressive tools sparked my interest in programming languages a long time ago. You hear developers talk a lot about programming languages (a nasty remark on Java in a news group will always trigger a flame war), but it takes a lot of effort to learn all these languages. I've been looking for a book that explains many languages with plenty of examples, assuming that the reader is familiar with at least one or two of the mainstream programming languages. Eventually, I've started collecting this information myself. You find the current state of this book on this site as html or pdf.
Please, send me any kind of comment as you read the draft. I'm particularly interested in comments on the less well-known programming languages (corrections, better explanations, more examples). I really appreciate your input (and there is still room in the acknowledgement section).