i have been collecting since may/june of 2005, and my collection is now worth (calculated everything on an excel spreadsheet): $4,798.55. i used to have every MSF mac ever made, and have sold a lot. but still! tons of money, haha.
i've been collecting mac for about 5-6 years and once at work we did a rough estimate as to how much i had spend on mac... it was a rather large total but luckily it was reasonably on target with my £50 a month budget.