Many tools are available for reformatting alignments, for example:
In addition most alignment editor/viewers can reformat alignments (see http://en.wikipedia.org/wiki/List_of_alignment_visualization_software).
FWIW there are some multiple sequence alignment programs that can produce multiple output formats per run, for example T-COFFEE produces multiple formats by default.
As the OP mentions supporting multiple output formats per run, is a useful feature and something I have requested for Clustal Omega in the past. I suggest any users who want to see the feature in a future version of Clustal Omega register their interest by letting the Clustal developers know by sending a request to clustalw@ucd.ie (see http://www.clustal.org/omega/#Contact).