A skill that you have, but has little to no benefit for you

Most of us have these little things we are able to do, that are a little different or special. Maybe it is something we mostly use in laid-back social situations, to break the ice and get a laugh. Beyond that, however, this talent does not do much for us. It is clearly not anything we would ever list on a resume. What might you call it?

Intended use:

Mike's family knew he was finally recovering from his injuries when he resumed his _______ of turning everything into a corny pun, which made his nurses laugh.

Another possible use:

Alice: (sticking out tongue and touching it to tip of nose) Tada!

Bob: Wow. Impressive.

Alice: Thanks, but I know that with this _______ and a dollar I can get a cup of coffee.

Candidates considered:

Hobby: On the contrary, your hobby can be of tremendous benefit to you. It is fun for you, releives your stress, and lets you have a sense of accomplishment. (reject)

Antic(s): For me, this has too much of a connotation that you only do the thing to create havoc or to tease another person. (near-miss)

Trick: In the absence of other options, this is what I might go with. However, this still doesn't quite sound right when I read it back. (debatable near-miss).

Despite this, feel free to propose any of these as answers if you can cite definitions and usage examples that refute my objections.

Final word: This is tagged with both single-word-requests and phrase-requests. All things being equal, a single word will win. However, where a short multi-word phrase tells the story better than one word, then so be it.

Perhaps an English term borrowed from Yiddish, schtick (or shtick, or shtik)

A characteristic attribute, talent, or trait that is helpful in securing recognition or attention: waiters in tropical attire are part of the restaurant's shtick.

American Heritage Dictionary

The term is often applied to a comedian's signature style or routine.

I'm not sure it matches your first example, but I feel it matches your description and second example, I'd suggest party trick.

Oxford Dictionaries describes it as

A trick such as might be performed at a party for entertainment; an unusual act regarded as one's speciality.

What do you think about gimmick? Though not always something that you do, a gimmick has the connotation of being a feature which superficially attracts attention or but has no real or practical value.

gimmick (n)

a method or trick that is used to get people's attention or to sell something

Although not exactly something one might do (at least not always willingly), I think quirk fits your description:

a peculiarity of action, behavior, or personality; mannerism;

in dictionary.com

I know there is already an accepted answer, but knack might fit.

Mike's family knew he was finally recovering from his injuries when he resumed his knack of turning everything into a corny pun, which made his nurses laugh.

In Alice's case, she would have a knack for performing odd physical feats.

m-w definition