UPDATE: I didn't think of it, but apparently the Memory Usage I see on VS indicates the amount of memory used by Resharper. I'm sorry if I offended anyone by this post - I don't mind picking on people and things here and there, but not when I'm wrong...
Did you ever notice the note on the lower left side of VS2005 window? At the moment of writing this post it says: "Memory Usage: 53.1 Mb". Sounds good, doesn't it? A quick look at the Windows Task Manager for the devenv process tells me the true story:
Mem Usage: 273,028
VM Size: 231,884 (note that this is the better measurement to assess how much memory is used by your process).