Frugal February, Round 2

I'm doing Frugal February again this year.  You can read about the background here.  Last year I had seven rules to follow to eliminate my impulse spending.  This year I'm doing a bit of tweaking.  I will retain all the old rules and add some new ones.

New rules:
1.  I will try to drink mainly water to reduce my expenditure on drinks.
2.  I will try to eat fairly cheaply without letting my diet fall to crap.  Last year I did not limit myself on grocery expenditures and spent about $108 on food.  I'm pretty sure I can drop this to $90.  I might try to eat some food that's been on the shelf in my house for a while.
3.  I'm allowing expenditure on Valentine's day stuff, but nothing extravagant.  Definitely under $20.

CAVEAT:  I am exempt from these rules if I get a flyout.  A flyout is basically a day long interview/campus visit for a university that is interested in hiring me.  The exemption lasts from the day before I leave until the day after I return.  At my discretion I may make up for these days by extending these rules into March.
...and by the way, I realized that I have a multi-day teaching conference to attend in February that's a couple hundred miles away...I'm going to allow gas for that.