Working around Exchange Webmail / OWA constant logoffs

I've always found that Exchange's webmail system, aka "Outlook Web Access", to be extremely buggy regarding remembering who you are. It sets sessions cookies with a pretty far-away timeout but regardless of whether I'm connected via a VPN or from the public internet it always delights in logging me out as quickly as it can. Well, I've worked out a work-around for these all too frequent occurrences. Here's what you do: