In online shops, you'll sometimes find offers that look too good to be true - very inexpensive USB sticks offering a large amount of data storage of one terabyte or more, for example. 

Consumers should always view such offers with suspicion, experts say. Even if your computer suggests that the flash drive's memory actually matches its advertised capacity, a cheap USB stick can usually store much less data, sometimes even resulting in data loss, according to the North Rhine-Westphalia Consumer Advice Centre in Germany.