I'm currently a graduate student in physics at Purdue working in Scanning
Probe Microscopy. My perl hacking is mostly for fun, although I am, from
time to time, actually paid for it (and wouldn't mind being so again :)
Judging from the ads I see, programming is likely to be more financially
rewarding than a career in physics, especially for the first decade of
employment. On the same subject, the American Physical Society has various
recent studies of salaries online. I don't have the link offhand but it
shouldn't be too hard to find.
If you're looking to maximize cashflow while programming you should
consider writing Perl code on Wall Street. Those guys also have recently
acquired a hankering for physicists so you could get your scientific degree,
code Perl, and make lots of cash, all at once.
<pause> <blink> Hmmm ... <scott wanders off gazing into the distance>