  The classical Ulam sequence is defined recursively as follows: $a_1=1$,
$a_2=2$, and $a_n$, for $n > 2$, is the smallest integer not already in the
sequence that can be written uniquely as the sum of two distinct earlier terms.
This sequence is known for its mysterious quasi-periodic behavior and its
surprising rigidity when we let $a_2$ vary. This definition can be generalized
to other sets of generators in different settings with a binary operation and a
valid notion of size. Since there is not always a natural linear ordering of
the elements, the resulting collections are called Ulam sets. In this paper, we
study Ulam sets in new settings. First, we investigate the structure of
canonical Ulam sets in free groups; this is the first investigation of Ulam
sets in noncommutative groups. We prove several symmetry results and prove a
periodicity result for eventually periodic words with fixed prefixes. Then, we
study Ulam sets in $\mathbb{Z}\times (\mathbb{Z}/n\mathbb{Z})$ and prove
regularity for an infinite class of initial sets. We also examine an intriguing
phenomenon about decompositions of later elements into sums of the generators.
Finally, we consider $\mathcal{V}$-sets, a variant where the summands are not
required to be distinct; we focus on $\mathcal{V}$-sets in $\mathbb{Z}^2$.
