Java

GridGain is an open source product written in Java providing a grid computing platform. It is known to be one of the more widely used grid product, certainly, as far as I see, one of the easiest to "gridify" or grid-enable an existing product.

One of the applications of the product is to couple with Amazon EC2 to make a "cloud" computing platform. See Gridgain + Amazon EC2

The widespread use of "multi-core" PCs also means that the product can be used to "parallelise" to take advantage of this increased power.

1. Use Native Methods: The small amount of overheads caused by JNI is usually outweighed by the improved speed of the native function
2. Use Buffering on I/O Operations: BufferedInputStream, BufferedOutputStream, BufferedReader, BufferedWriter reduce the number of I/O operations to be performed.
3. Avoid Creating New Objects: Reuse objects as much as possible. The more objects, the more memory to create/store them.
4. Use StringBuffer instead of String Concatenations