I am a salaried employee in technology.  I am married and we have no
kids.  Wife is an artist (painter).  We do not own a home.

Obviously, the standard tax shelters/hacks (mortgage interest
deduction, child tax credit) do not work for us.  Is there any other
way we can minimize our taxes paid beyond a 401k & IRA contribution
(really only 401k since it's maxed out)?

Without knowing more about your situation, it would be difficult to
suggest a course of action.

If buying a home and/or having children is out of the question, there
are still a great many ways to take deductions.  Buying a hybrid car
can get you a $2000 deduction, for example.  You can also choose to
donate to charity; the reduction in AGI could put you in a lower tax
bracket.

You can also look at other ways of keeping more of you income, such as
cutting uneccesary expenditures from your budget.

Even while maxing out a 401k you may still put money into an IRA.  

The contribution limit in 2004 is $3,000 per individual, so that is
$6,000 total for you and your wife (assuming you each individually
have an income of atleast $3,000).  In 2005 the limit will be raised
to $4,000 each.

Alex brought up some good points as well, but frankly death and taxes
are unavoidable.  If you make enough money to max out your 401k and 2
IRAs and still have enough money left that you want to avoid taxes
with then I envy your earnings :)

Best of luck in your search to avoid Uncle Sam (I avoid him all that I
can as well), but do keep in mind everything that he provides for us
as well.