How can I combine multiple files into a single larger file on a non-virtual filesystem?

Is there any filesystem where I can say map file1, file2, file3 and file4 together to file1234? file1 is 100M file2 is 100M file3 is 100M file4 is 100M ... and file1234 will then be 400M, and it is safely stored in this filesystem? not a virtual-filesystem, it must be saved at filesystem.