BmpWrapper

This app converts any file to a BMP image and restores the original file from the BMP.
Some email server may check the attachment of a email to see whether it is a dangerous file (especially .exe, .dll, .so ...). If you are fortunate enough, some stupid server will let you pass through if you just modify the extension of a file.
For those servers which will really examine the file format, this app may help since most, if not all, of them won't reject an image file.
Last but not least, this app contains an encryption function so that you can encrypt the embedded file inside BMP before sending out.