Yes why spend more than $150 on an 2GB ipod nano when you can get a 4gb nano clone mp4 for less than $75 ... and what else ipod nano can play only music and view pictures , where as MP4's can play Video , music , Games , Text , pictures , has a voice recorder(built in mic) , FM recorder and radio.
s1mp3 a Chinese company is one of the largest producers of mp4's today . Mp4 players are cheap and range from 64mb up to 30 gb (and above) , they are also available in different shapes (like cubes and spheres ) and various functions (i saw one mp4 with a camera ,tv capture function ,built in speakers and double earphones sockets ). Mp4's usually come with fake labels on them like SONY . Best buy the latest s1mp3 player for more details check here http://www.s1mp3.org/ . You also have to download the video converters from here . You can even buy s1mp3 mp3 players only the play music , Fm have a voice recorder and have a b/w display available as low as $25 . Even check out http://www.iriver.com/ a different brand
NOTE: i recommend you buy the latest mp4's as some of them are delicate and the usb break's easily . You have to be careful with the thin and small one's.