Stripping Unnecessary Data from Files in Linux

[Xcellerator]

I'm working with a Teensy++ 2.0 board which only has 128K of onboard flash memory. I'm using it as HID + Disk, so as well as program that contains the keystrokes, I also have it doubled up as mass storage. The files I need to on the disk ever so slightly exceed the limit. I literally need to lose a couple of K.
Is there a way of stripping out the unnecessary data from the files? Like all the NTFS permissions that windows uses (I'm in Mint now - no longer windows), and other data?

Thanks in advance for any advice..

[vector]

what type of files are we talking about here?