A tutorial on Gamedevtuts+ on chosing a color palette for your models and some useful tools o create a palette.
This tutorial by web site KatsBits explains how to get alpha-channeled transparent textures with Blender 2.5+ right.
“Getting alpha-channeled transparent textures to correctly display in Blenders main 3D View has always been a bit tricky to do because of the ‘real time’ nature of the feature. It needn’t be however, as the following tutorial explains, it is generally and relatively straightforward to get semi-opaque or fully transparent textures set-up to display correctly depending on the type of transparency required in the main work zone. The following tutorial discuses the two main approaches to getting transparency to correctly display in the 3D View.”
GLC_Player is a free software used to view 3d models in the COLLADA, 3DXML, OBJ, 3DS, STL, OFF, COFF formats and to navigate easily in these models. With the album management, capture and multi-capture capabilities, html export and navigation possibilities GLC_Player is the accurate tools to review a lot of 3D models and to create illustrations. GLC_Player is a cross-platform application for Mac, Linux and Windows.