An special case in the list below is the mention of the SpaceToad's Buildcraft transport pipes, while not being directly related to BTW, the implementation of the RP2's tubes were one of the main reasons for FlowerChild to decide leaving the Forge.
All versions cited bellow provides a link to the release announcements.
The full changelog of Better than Wolves can be read here. It includes release dates starting with the version 2.66.
The full changelog of RedPower and RedPower2 can be read here. Release dates starting with RP2 PR1 can be confirmed in her RP2 blog, that is up again.
FlowerChild's Better than Wolves
Eloraam's Red Power and Red Power 2
SpaceToad's Buildcraft
Device Name: Saw / Hand saws
Basic Functionality: Sub-blocks crafting.
Differences: BTW's version is a block, capable of cutting wooden blocks only. RP version is a crafting table item to make microblocks of any material, it exists in five varieties and wears off by using it.
First appearence: BTW2.20 for MC beta 1.5_01 (May 27th, 2011) / RP 1.7.0 for MC beta 1.7.3 (August 25th, 2011)
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Functionality: Plant, no world-generated, two blocks growth, provides fiber.
Differences: BTW's hemp is processed into fibers for crafting of rope and fabric. RP's Flax is a non-spidey source of string.
First appearence: BTW1.60 for MC beta 1.5_01 (May 6th, 2011) / RP2 PR1 for MC beta 1.8.1 (October 2nd, 2011)
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Functionality: Contained item transport.
Differences: Pipes can be crafted in with different materials and with special properties for each. Tubes came in a single generic kind.
First appearence: BC1.0 for MC beta 1.5_01 (April 25th, 2011) / RP2 PR1 for MC beta 1.8.1 (October 2nd, 2011)
Images:
Functionality: Block that creates fire, toggleable. Special notice in the similarities of the textures.
Differences: The Hibachi creates fire on the upper face of the block. The Igniter can be rotated to provide fire to any of its faces.
First appearence: BTW1.0 for MC beta 1.4_01 (April 10th, 2011) / RP2 PR4e for MC 1.2.3 (March 17th, 2012)
Images:
Functionality:Movable blocks. Special notice in the similarities of the textures.
Differences: BTW's Platforms allow vertical movement when used in conjuntion with anchors, rope and pulleys. RP2's Frames can be moved horizontally or vertically using Motors.
First appearence: BTW2.60 for MC beta 1.6.6 (June 15th, 2011) / RP2 PR5 for MC 1.2.5 (April 21th, 2012)
Images:
Functionality: Power producing devices.
Differences: BTW's Windmills and Vertical Windmills produce mechanical power, RP2's Wind Turbines produces blutricity and the windmills wear off by use. The BTW's Vertical windmil was designed to provide mechanical power in the Nether. Note that after BTW's Vertical Windmills were released, an image of regular and dyed "work in progress" version of RP2 windmills was leaked.
First appearence: BTW2.31 for MC beta 1.6.6 (June 1st, 2011) / BTW4.30 for MC 1.4.1 (October 25th, 2012) / RP2 PR6? for MC 1.4.6? (first image shown on October 7th, 2012, the image with horizontal windmill was shown on October 29th, 2012 the version with both was released 2 months later RP2 PR6 for MC 1.4.6 (December 21th, 2012)
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