The Header and Envelope rewrite mini-HOWTO explains how to rewrite your from address differently in the mail header and the mail envelope. This may be necessary, for example, if your ISP requires you to send mail with one address, but you are subscribed to mailing lists with a different address, or want others to see a forwarding address instead of your ISP's address.
LavaPE is a programming environment for the experimental object-oriented programming language Lava. It replaces text editing with structure editing, thereby preventing all syntactic and many semantic errors. The pure point-and-click nature of Lava programming and the concise representation of programs as declaration trees with small chunks of executable code simplify programming, and ease comprehension.