I find the use of the Mercator projection to portray the world offensive in any context (as it hugely distorts the sizes of countries and continents, Greenland isn't really larger than South America, it's a lot smaller!), but in the context of trying to help developing countries (which all appear small and insignificant in this projection) it really drives me up the wall.
Apparently, applications that allow you to zoom in and out of maps, like Google maps routinely use the Mercator projection, as this is the easiest one to calculate (it’s all in squares), but that’s no excuse for displaying the world in a blatantly misleading way, as, for instance, Oxfam does here:
Food price volatility map
I am sure the clever people working at Google and other internet companies can come up with a way to program interactive maps without making tropical countries shrink to insignificance?
If one has to have a cylindrical projection (where all the longitudes and latitudes are straight lines), one could use the Gall-Peters projection:
which with its very unfamiliar look reminds us how wrong the maps are that we see more often. Personally, I prefer the round or oval projections, as they also remind us that our planet isn't rectangular, e.g. the Lambert azimuthal equal-area projection.
PS checking up on Google I realised that even their satellite view is in Mercator projection. Surely the satellites don't observe a cylindrical planet from space?