Hi PPierians :)
This is no great shakes but I don't see why other people should reinvent the wheel so here is a Windows script I made to back up my PP site.
The folder it backs up to is created based on the date the script is run, so is suitable for a maximum frequency of daily backups (if you want to backup more than once a day you could modify the script to add in the time perhaps).
Hope it proves useful to someone.
::change backup path and xampp path to match your setup as required
::backup pp database to a file
%xampp%\mysql\bin\mysqldump -u root pp > pp.sql
::backup some useful ini files etc
xcopy /Y /I /R %xampp%\mysql\bin\my.cnf %backpath%
xcopy /Y /I /R %xampp%\mysql\bin\pp.sql %backpath%
xcopy /Y /I /R %xampp%\apache\bin\php.ini %backpath%
::backup the entire pp folder - that should cover most bases :)
xcopy /Y /I /R /E %xampp%\htdocs\pp %backpath%\pp
::"clear" the cache