I work in cluster computing and am using Mac OS X 10.6. I send off hundreds of computing jobs a day, and each one comes back with with a different extension. For example, svmGeneSelect.o12345 which is the std output of my svmGeneSelect job which is job number 12345. I don't control the extensions. All files are plain text. I want OSX to open any file extension that it hasn't seen before with my favorite text editor when I click on it. Or even better set up file association defaults for extension patterns ie textEdit for extensions matching *.o*. I do NOT want to create file associations for individual files since this extension will only ever exist once, and I do not want to go through the process of selecting the application to use for each file. Thanks for any help you can offer.