Port of example code from http://www.scala-lang.org/api/2.10.4/#scala.util.control.TailCalls$ to Trampoline. Note that for this example, Eval is probably more efficient.

trampoline.scala

import cats.free.Trampoline, Trampoline._
import cats.implicits._

def isEven(xs: List[Int]): Trampoline[Boolean] =
  if (xs.isEmpty) done(true) else suspend(isOdd(xs.tail))

def isOdd(xs: List[Int]): Trampoline[Boolean] =
 if (xs.isEmpty) done(false) else suspend(isEven(xs.tail))

// returns true (doesn't overflow the stack)
isEven((1 to 100000).toList).run