Hello! Nod32 4 and Eset Smart Security 4 will be have scan after pluged flash drive to usb port. This is very good extension. Can you make it to avast? Please dont take this topic like advertisement.
USBVirusScan will launch any program you provide as a command line parameter each time a USB stick is inserted. I use it to start a full virus scan on the inserted USB drive: http://blog.didierstevens.com/programs/usbvirusscan/
The command-line that worked for me is:
“\USBVirusScan.exe” -c -i “\avast4\ashQuick.exe” x:
Where you need to change the for the both correct ones and the x: for the letter of your USB drive.