If you want to do some casual research for a future trip, you can get fare estimates using the Kayak skill. You can say, "Alexa, ask Kayak where I can go for $400" or "Alexa, ask Kayak how much it costs to fly from Los Angeles to Dublin." The skill will ask for additional information and eventually provide you with a series of options and price ranges.
Because Amazon opened up the development of Alexa Skills to anyone with the free Alexa Skills Kit (ASK) in 2015, anyone can create an Alexa Skill. As Alexa uses Natural Language Programing (NLP), those looking to build a skill don't need to worry about complex speech recognition. The ASK tools also makes it easier for novices to work with sophisticated NLP ideas.