Unix commands comparison
You may find the comparison table is useful when you port applications, though some commands in the table are out of date. Anyway, it's still handy as a quick reference.
Another interesting stuff on this web site is the poll of "the best OS". To date, 13K people voted. The top three OS are: Linux(~26%), Solaris(~21%) and AIX/Tru64(~15.5%). So, vote your favorite if you like.
