There are several options for sub-light propulsion currently in high use. The most popular among these include the Angst Drive and the TTOAM Drive.
The Angst drive is quite popular due to its intense power supply, this being derived from the ire of teenagers and adolescents throughout the galaxy. The main reason for the popularity of this drive is its accelerative properties. The greater the angst in the universe, the greater the amount of immediate power available to the Angst Drive’s core. While it does provide great propulsion and phenomenal acceleration, it is not quite as reliable as one would like in a main system drive. The overwhelming majority of the time, it will work flawlessly, as most teenagers are in a constant state of angst. Occasionally, there will be a lull, and a time of adolescent peace will outweigh the power of the angst in the universe. At these times, the Angst Drive powers down completely, rendering all space-faring vehicles relying solely on these drives completely inert. Thankfully these times are rare. However, due to this slight limitation, regulations are now in place for ships with the Angst Drive as the main propulsion drive to maintain a secondary engine type not reliant on the feelings of the universal youth population.
The second quite popular drive is known as the TTOAM (pronounced ‘tome’) drive. While this drive is not as quick to accelerate as the Angst Drive, there is a constant power supply. TTOAM (Take Them Out And Measure) drives are powered by the incessant need of the male derivation of many creatures to display their greater maleness to other males. This drive is not wholly powered by the Human population in the universe, but Humans do make up quite a bit of the power supply. Thankfully this force of nature is inherent in the male population of most living things throughout the known universe. This engine is not as quick to accelerate as the Angst drive, however, due to the fact that the TTOAM urge itself is a constant, and not as prone to sudden outbursts. The high reliability of this engine is what makes it so popular. There is no need for a backup drive or additional propulsion when this is the primary drive. If a ship finds itself wandering too far from an inhabited galaxy, one only need initiate a small challenge among the crew to create a mobile power supply. Typically this will take the form of an arm-wrestling match, a card game, or an intellectual contest of some ilk. Rock, Paper, Scissors has proven to be quite powerful as well. The possibilities are nearly endless.
A new drive currently in testing is quickly gaining popularity as well. There are several derivations of this drive currently being researched, thus it is known by many different names. Technically called the “Do-you-believe-what-that-bitch-just-said-to-me” Drive, it is most commonly referred to as the catfight drive, it is quite similar to the TTOAM drive, though it combines the quick acceleration of the Angst drive as well as the reliability of the TTOAM. This drive is fueled by the female human population’s need to fight amongst themselves about seemingly innocent matters. Often started by such comments as “Oh, I just loved that dress when I got it last year” the catfight is both constantly powered by intellectual slapping and clawing matches as well as deeply buried anger, thus providing a high powered, highly reliable, quick to accelerate machine. Unfortunately, it is also highly unstable. It is not uncommon for these drives to burn out from too much power being funneled into the system at once. It is for this reason that all ships currently testing the beta versions of these drives must travel in pairs. The only way to repair a burnt out Do-you-believe-what-that-bitch-just-said-to-me drive is for that ship and another ship with Do-you-believe-what-that-bitch-just-said-to-me drive to apologize to each other, and have a good hug after it’s all over with. Research is underway to store the excess unstable energy in an “It’s-OK-I-don’t-even-know-why-we-were-fighting” buffer to maintain stability and lower occurrences of burn out.
At one time there was a line of research into the possibility of using the endless supply of Snarky on the Internet. All Internet- and media-based power was found unreliable, however, due to Wikipedia, MSNBC, and Fox News. The latter two sources, however, led to other technologies (see Gravity Fields). There are still many Snarky drives available on the black-hole market. Snarky-powered engines are not nearly as useful as one might imagine, due to the simple fact that the Snark used must be genuine, not rhetoric simply created to fill a forum or blog post.
 Use at your own peril. This creators of this document not responsible for loss of life, limb, or sense of humor or tact.