afni.nimh.nih.gov

There is (as far as I can see) no limit on the number of LINES in a 1dMarry file. There is a limit of 26 on the number of values (from separate files) that can be married together, but each input file can be as long as you need.

The upper limit of 26 partners in a marriage is arbitrary, but I can't really conceive of what application you'd have for such a giant grouping of numbers. My mind boggles out at about 4 numbers per time point.