I just did a google image search for "sexy mouse pad" and frankly, I'm too embarrassed to post any here.
Definately not "sweet", and to me not sexy, but rather cheezey or sleazey.
Then again, I've never been one for sex gifts, but, that's just me.
On a serious note, Valentine's Day is one of those manufactured holidays designed to make us feel obligated to buy something, at the risk of appearing "unromantic"
I think the best gift is a big hug, and a sincere "I love you"
That can be given any day of the year, and one size fits all.