William McHale wrote:

I don't think anyone is arguing that we shouldn't have a budget, but rather
that the budget should not be cut off arbitrarely.

When it comes down to it, science never can be justified on the basis of return
on investment a priori to any discoveries that might be made.  There is simply too much uncertainty involved.  On the flip side, we know that the more we invest in science, the more discoveries we are likely to encounter and some of
them almost certainly will be astounding.

I totally agree. Looking at Voyager probes' site at http://voyager.jpl.nasa.gov/ I read "Both spacecraft are still going strong and are returning valuable science data."
One should consider also we're not going to have other probes to such a distance for decades, so abandoning Voyagers seem really disturbing to me. After all, if NASA really lacks money, there should be another option, like a cooperation with another space agency like ESA.
Asking for a public donation should also without doubt find enough money : just visit http://www.saveenterprise.com and you'll see that millions of dollars are collected to save Star Trek...