> Does anyone have any experience of doing this kind of thing? Anyone got
> any hints as to whether sending 200,000 individual emails (i.e. not the
> same email to everyone) within a 4 hour timeframe is feasible, and what
> sort of machine we'd need to do it (we use Sun's)?
If you have some cash to put out, take a look at L-SOFT (www.lsoft.com). With LISTSERV and LSMTP and a P200 with 256MB, you can put out about 700,000 emails in 4 hours, provided you have the bandwidth. They have versions for various o/s's. If output is what you desire, this is the software.