I'm in the process of designing a new system which needs to scale well and be as cheap as possible.

The application involved is fairly basic but will need to be able to handle short periods of very intense use. Say 100k users trying to log on during the course of a single day. The actual data stored in the database on a per user basis will be fairly simple, so most database access should only consist of a handle of queries per user.

Realistically how many servers, megs of ram etc do you think I will need at a minimum to achieve this? Including some basic redundancy etc.

I'm sorry if this sounds a liitle vague but I'm only sure of these scant details so far.

I'm be very interested to hear your ideas on this, or experience with a similar requirements.

Thanks in advance,