I have to spend a fair bit of time at work hacking away on Solaris boxes and have really started to miss some of the extra features of many GNU tools I really took for granted. One that really bugs me is the lack of in-place editing in Solaris sed (-i using GNU sed). Perl to the rescuse!
perl -pi -e 's/foo/bar/g' /path/to/file
The above is pretty functionally equivalent to sed -i. A quick alias in .bashrc:
alias sed-i='perl -pi -e'
and everything in life is well again.