The best place to find many different great designs is over at the Factorio Blueprints website. This section is just for showing some of my personal favorites that seem to work very well. All of the designs shown here and many more can be found at the Blueprints site.
Important: To use a blueprint string to import the blueprint into your own game, you will need the Blueprint String Mod located here. Instructions for using the it are in the forum post for the mod.
Solar & Accumulator Layout
One of the most popular Solar and Accumulator layouts, which was created by MadZuri. The ratio of Solar Panels to Accumulators is nearly perfect, and it also included a Roboport in the design!
More info and blueprint string can be found here.
Octagon Red Circuit Build - Robot Verison
A great Red Circuit build that uses the correct ratios and is Logistic Robot compatible. There is also a similar version using belts that will be listed later on.
More info and the Blueprint String can be found here.
This neat setup is very compact and has optimal ratios for all four types of science. It features 5 Red Science machines, 6 Green, 12 Blue, and 1 Purple. These ratios should produce 1 per second.
More info and the Blueprint String can be found here.
A Smart 2 wagon train loader using some Smart Chests, Smart Inserters, and a Combinator.
It auto balances the chests by loading or not loading them based on the amounts in each chest. More info and the blueprint string can be found here.