How can I `cat` files with a number of fixed lines before/between/after?

I am looking for a bash one-liner which can cat a number of files with a number of fixed lines. file1.txt: file1 line 1 file1 line 2 file2.txt file2 line 1 file2 line 2 Then I am looking for something like cat-with-strings foo file1.txt bar file2.txt baz producing output foo file1 line 1 file1 line 2 bar file2 line 1 file2 line 2 baz How can I do this in a single line of bash, using standard linux tools (sed, awk, cat, etc) and *without* creating any files to hold foo, bar, or baz?