Well, I certainly understand where Jeff is coming from.
There are various frustrating factors which, I suspect, may decrease in the upcoming years.
One major one has to do with the whole web application arena.
Not all web application developers write portable code.
In some cases, the authors never think about there being anyone other than a Windows Internet Explorer user. In other cases, they know others are out there, but either don't care, or don't consider it a high priority. Finally, in a very small number of cases, the developers do recognize there are others out there, and do care, and go to extraordinary efforts to support at least some degree of cross platform capability.
The latter group are a wonderful bunch. It's the first two groups however, that dominate the web landscape, in my experience.
In many of these cases, however, Linux plus the latest browser plus the latest of a few well chosen plugins will work well enough to get by - sometimes even in SPITE of intentional efforts by web developers to turn legit users away when they don't use hardware and/or software identified as 'supported'.
Sometimes, one can find alternatives that are acceptable. Sometimes, that is not possible.
I wonder if, for Jeff, there is any sort of Windows emulator under which Windows Internet Explorer could run to access the site, or sites, which don't work for him normally.