The Prophet Muhammad (peace be upon him) said:
“Charity is prescribed for each descendant of Adam every day the sun rises.”
He was then asked:
“From what do we give charity every day?”
The Prophet answered:
“The doors of goodness are many…[encouraging] good, forbidding evil, removing harm from the road [so that travellers are safe], listening to the deaf, leading the blind, guiding one to the object of his need, hurrying with the strength of one’s legs to one in sorrow who is asking for help, and supporting the feeble with the strength of one’s arms — all of these are charity prescribed for you.”
He also said:
“Your smile for your brother is charity.” 
Purim is approaching.
We’re expected to give tzedakah — charity.
The first thing people think of as “charity” is money. Give money. Lots, if you can.
But some can’t.
What do they give?
In Torah we’re told to bring a bull to the Temple as an offering. If we can’t afford a bull, bring a sheep. If we can’t afford a sheep, bring a goat. If we can’t afford a goat, bring a bird. If we can’t afford a bird, bring a handful of grain.
What, then, of one who has no grain to give?
Let him, or her, help another.
What, then, of the one who is unable to help? The one who can’t walk or lift or carry?
Let him, or her, smile.
Give a smile to all around you.
There is no one who doesn’t need a smile, even if it seems unappreciated.
If you’re in a hospital, or nursing home, or assisted living facility —
Smile at all those who live with you. Not just those you always smile at, but at all those who are there.
Especially — smile at those who work there.
Smile at nurses and aides. Smile at recreation workers. Smile at kitchen staff. Smile at clerical and administrative staff. Smile at custodial staff and at all others who are caring for you.
The prophet Muhammad said, “Your smile for your brother [or sister] is your charity” — your “sadaqah” (the Arabic form of the Hebrew “tzedakah“).
Let it not be only a “polite” smile. Upturned lips, a perfunctory nod. Cold heart.
Let the love that is in your heart — love that gets covered over with remorse or resentment or resignation or routine — emerge. Let it emerge slowly and carefully, like a new bud in Spring, if you need to do it that way. Let it burst like a fountain or geyser, if you’re able. Let its warmth, and your celebration of the Divine Goodness that resides in you and in all those you see and in all that happens around you, fill your heart with feelings of safety and trust.
Your smile is your tzedakah.
The world needs your tzedakah.
The world needs your smile.