Are bandwagon goods an exception to the law of demand, by the way? To me it makes no sense. Veblen goods yes, but bandwagon goods are as such because "everyone else is buying them". It's precisely the opposite of veblen goods. They are intended for the "mass affluent", and remind me of things like the iPhone or Playstation 3, which are luxury goods by any definition but derive their status because "everyone" has them.
Thus if the price decreases, the size of "everyone" increases, increasing the bandwagon effect further exacerbating the increase in quantity demanded. Therefore if anything demand is just more sensitive to downward changes in price...
My personal favorite is the giffen good, because you talk specifically about the income and substitution effects. It's the most theoretical of them all which I like, but I struggled finding real world examples (though I ended up talking about rice and meat in China).
Oh an offshoot of the Veblen good I briefly mentioned (and cited myself as evidence :/, hope its ok) is "consumer ignorance" I don't know if that's the term. I said even at a common, non "veblen" type restaurant, higher prices imply "better" things, and consumers have psychological ignorance and are predisposed to think that quality correlates with price. And I said I myself have done this at shoe stores, but I kept the writing pretty professional and dry and all.