The memory space (often in the form of cache) in a system (e.g., an Internet proxy or web browser) is conserved by saving low resolution versions of data objects when the full resolution version is removed (e.g., due to age, using a least recently used (LRU) replacement policy) in order to create space for new objects. This provides for efficient use of the memory space. In many situations, the low resolution version of the data object is of adequate quality for usage. Further, even when this is not the case, it can be useful to quickly obtain a low resolution version and then with some delay, obtain the full resolution version at the user or application's request. Particular advantageous embodiments of methods, apparatus and article of manufacture implementing the invention are presented.