It seems that puTTY dumps crap in the root folder.
Volume in drive C is Local Disk
Volume Serial Number is 5C04-438C
Directory of C:
2004-05-26 11:25 600 PUTTY.RND
1 File(s) 600 bytes
0 Dir(s) 27,420,908,544 bytes free
Also, does anyone know what a .SDO file is?