Iframe for external sites

It would be very useful to be able to define a link that will open inside intervals as an iframe -- so project web sites sites that are under development can be viewed as well as any other external link. The system at weboffice handles this very well. You can check it out at https://www.webexone.com/lp/200705/projectmanagement.asp?adid=GC$WOWENCATCOLL~10.06.008$LS=A_LP

I found that to be quite useful -- that coupled wtih your current structure is of tremendous value to us web development shops.