If you are only using one card reader or one memory card, this tip is of little use to you. But if you are using several cards or several readers this is a real time saver.
I use SanDisk’s ImageMate All-in-One card reader which takes both my D3100 SD cards and my D300 CF cards. But up till now I used to read the cards one after the other, which was pretty annoying.
This 3 minutes video shows how you can read several cards simultaneously. This saves the hassle of key-wording or applying import presets twice, but more importantly, it saves the need to babysit Lightroom and wait for the first card to finish download.
P.S. B&H are having a huge one day sale on sandisk cards, so if you need more space…