Rubber is the basic component in most Industrial Craft 2 recipes obtained by smelting Sticky Resin in a Furnace or an Extractor. The Extractor is the most efficient method, but it requires Energy Units (EU), so making it in a furnace is your only choice when starting out. Rubber Wood (both the Industrial Craft 2 and RedPower 2 versions) and saplings can also be converted into Rubber using an Extractor, but they yield significantly less Rubber. Rubber is primarily used in the creation of cables.
Many stacks of rubber are required in order to efficiently produce large quantities of advanced machines, so making a rubber tree farm is recommended.
An automated MineFactory Reloaded farm using IC2 Rubber Trees is likely to fail due to a sapling shortage. It is, however, possible to use MFR to auto-farm RP2 Rubber Trees to great effect, given enough space to grow. This forum thread gives some vital information on how to make this work.
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