You can cycle tanks smaller than a 5 gallon. Go on to any planted tank forum and these people have some seriously expensive and sensitive species of fish living in small tanks that have been completely cycled.
What you need in a small tank is a filter with a large surface area so as much bacteria as possible can establish itself. This is important because of the rate in which ammonia and nitrite build-up in small aquariums. I also recommend using fast-growing live plants such as floaters or stems as these help stabilise your cycle by consuming excess ammonia and nitrates.
If you are not comfortable with the idea of cycling your tank, simply don't put in a filter and stick with doing regular water changes instead. While cycling is more work at the start, once your cycle has established itself, your tank will not need as much regular maintenance as one that is uncycled.
However, for those new to the concept, it is sometimes easier just to do 50-100% water changes every few days than to have be fiddling around with test kits and water changes for 4-6 weeks.