How can I estimate the loading speed for my URL at differnt connection speeds?

[SteveSki]

I'm building a new website that is graphic, video and audio intensive and need to determine what the average loading times will be on different browsers and ISP connection speeds. I remember seeing a site somewhere that would show you the load time for your url but can't find the address. Can anyone here point me to a tool like that?

Thanks,
Steve Shulenski