I have yet to try any new Lenovo because they all come with Vista or Win 7 which are both terrible with their heavy memory overload.
Well, not quite (on both points). Many T60/T61 (and contemporary machines) came with XP or an XP downgrade option. Not to mention that you can still always install XP, even on the newest machines (not that I would recommend that since Vista/Win7 are better operating systems at this point).
As far as memory overload - that's also a common misconception. Vista/Win7 allow better utilization of available system memory for application caching. So it will seem like you have less free memory, but it's designed to improve performance (the feature is called Superfetch). And in any case it can be disabled, at which point the overhead over XP's memory footprint remains quite small.