Appearance
In the manga, Near is only ever seen wearing white pajamas, while in the anime, his pants are light blue.
In L: Change the WorLd, Near is a Thai boy and the sole survivor of a village ravaged by disease. In the live action film, he has black hair, while in the novel he is described as the original Near in the series (while I haven't read the novel I would assume this means he has white hair).
Personality
Near shows much more emotion in the manga than he does in the anime, particularly his facial expressions. A quote from the wiki shows an example of this:
When the SPK members were killed in the anime Near has a very stern look, but in the manga he is visibly upset.
His facial expressions were probably more towards his smiling when he got things right, which was used to foreshadow the end where he smiles after seeing Ryuk, confirming to himself that Light is Kira.
Source: Death Note Wikia site