Storing A List In A Database Table (messaging Queue?)

hey all you database guru's hopefully someone can lend some insight as to a little table design problem I have.

Basically I've got a system in place to authorize users to access a website typical username password stuff. The table contains a list of users and there passwords plus the auth level and a few other tid bits that aren't really important enough to into detail about them here. What I want to do is add a messaging system to this, I think I could probably figure out a way to do this half decent if I setup a seperate table for each user to add a row to the table for every message entry than in my asp.net code have it delete everything but the last 10 entries every time a user logs on. However I would much prefer a way that I didn't have to setup a whole new table for each user just for messaging purposes, maybe store something like a list in one of the database cell's kind of like .nets generic.list or better yet generic.queue, I would also like a way if it's possible without too much work to have the table automatically delete the oldest message every time a new message is received if there's already 10 messages existing for the user.

Anyways hopefully someone has some experience in setting up a system like this, I don't really require any code samples I can code it all myself (other than the database code to automatically remove entry's, I'm not a database guy) if someone could just explain a way to accomplish what I'm trying to do, or if someone has a different more convenient way of doing this I would be up for suggestions


Thanks in advance for any help offered, I do appreciate it