Ever wondered how to create a back slash in VirtualPC whilst the Escape key for leaving the Virtual PC mode is AltGR? If you press the AltGR in Virtual PC, which is necessary to create a backslash, then the focus of the local machine gets lost.
Tip: The trick here is to use a similar key combination which has the same effect. Old DOS freaks might know that any ASCII code may be entered with (CTRL+)ALT and then a three digit number sequence of the ASCII code entered via the numerical key pad. In the case of the backslash this would be 092. Still this does not work in Virtual PC either. There is even a much simpler trick: You may hold down CTRL+ALT (on German keyboard layouts it is labeled “STRG” for Steuerung and “ALT”) and then press the ß-symbol (“Es-Zett”). This will give you the backslash you wanted to have.
Side remark: Please note that STRG+ALT is NOT entirely the same as the AltGR key as this comment might suggest it. However, in many situations the two “false friends” behave quite the same.