When interest rates fall, the price (NAV) of bonds and bond funds goes
up.  I'm looking for an investment vehicle that works inversely,
namely that the price of the fund or investment vehicle goes up as
interest rates rise.  Note: the interest rate of the underlying bond
isn't my primary concern here.  Instead, just like I can make 15-20%
on long-term bonds when interest rates go down 1%, I'd like to make
that much when interest rates go up 1%.  I prefer to go the simplest
route so I'd like to know first if there are any bond or mutual funds.
 If not, is options trading on bonds possible?

Short selling bonds, or bond indexes (ex: iShares) can get you the
desired result you are looking for.

You may be too late to the game however.

http://biz.yahoo.com/ifunds/040513/20040513_shorting_iss_etf_jb_2.html

This article (a month old, however) stated that many of the funds are
unavailable to be shorted.

Not everyone qualifies to be able to short securities or trade
options, a Researcher may have better luck finding out what is
available for you if you describe your level of trading access.

Also, any funds that short sell themselves would likely be classified
as hedge funds, which opens up a whole new can of worms and have their
own trading requirements.