adaptive-compression

What is the best compression algorithm that allows random reads/writes in a file? I know that any adaptive compression algorithms would be out of the question. And I know huffman encoding would be out of the question. Does anyone have a better compression algorithm that would allow random reads/writes? I think you could use any compression algorithm if you write it in blocks, but ideally I would not like to have to decompress a whole block at a time. But if you have suggestions on an easy way to do this and how to know the block boundaries, please let me know. If this is part of your solution,