One of the challenges of a terrarium is the struggle for light. Because it is indoors you might not be able to find a spot that gets a lot of light. This is ok though there are plenty of plants that thrive in low light conditions so if you live in an apartment, dorm room, office or a place with few bright light window options you can still make a terrarium that thrives. Here is a list of terrarium plants that thrive in low light:
Philodendrons - There are many varieties and most thrive in low light conditions
Peperomia Plants - This is a whole family of small plants that do well in low light. Good examples are the Peperomia Prostata and Miniature Peperomia
Pothos plants - are very hardy and pretty indestructible, they tend to grow a little big for terrariums though. Pothos Plants on Amazon.com
Bromeliads - is a whole species of plants with many varieties. Many of them are very hardy, thrive in low light and stay small enough for a small terrarium. Bromeliads on Amazon.com
Pilea Plants - This is a species of shade loving plants that come in a variety of sizes many of them are small and hardy. Some good examples are the Pilea involucrata and PIlea Nummulariifolia (Creeping Charlie) Pilea Plants
Pellionia - grows up to four inches in height, needs brightness but not direct sunlight
Sinningia plants are often very good, thrive in low light, flower and are very small Micro-mini Sinningia (sinningia Puilla) - This is one of the worlds smallest flowering house plants. Others are the white sprite, Snowflake, Dollbaby and Tinkerbell Sinningia Plants
Carnivorous Plants often do very well in low light conditions because they derive their nutrients from insects. Here are some good examples for low light terrariums:
Non Traditional Plants - There are plenty of options when it comes to thinking outside the box and a good example of low light plants that are not typical are like these: