Nephelium lappaceum

This is again a Dr Seus like crazy looking fruit  with small spines on the outside. it is a refreshing fabulus little fruit often sold on the roadside in Costa Rica and is closely related  to the lychee, longan, and mamoncillo.  

A species regularly sold in Costa Rican markets may be known as "wild" rambutan. Yellow in color, it is smaller than the usual red variety. The flesh exposed when the outer skin is peeled off is sweet and sour, slightly grape-like and gummy to the taste. In Panama and Costa Rican Spanish, it is known asmamón chino ("Chinese Sucker") due to its Asian origin and the likeness of the edible part with Melicoccus bijugatus. The fruit is non climatic which means it ripens only on trees. 

The fruit are usually sold fresh, used in making jams and jellies, or canned. Evergreen rambutan trees with their abundant colored fruit make beautiful landscape specimens.

http://en.wikipedia.org/wiki/Rambutan