As a food source:
Most people in the United States consider Purslane an invasive weed, but it is commonly eaten throughout other parts of the world. It can be prepared like most other leafy vegetables and contains more Omega-3 fatty acids than any other leafy vegetable plant. It has a salty / lemony taste that is less bitter than arugula. The leaves, flowerbuds and stems are great raw in salads. You can steam them, stir-fry them or add them to soups, stews, and other vegetable dishes. You can also pickle the green seed pod for capers.
As a companion plant:
Purslane makes excellent ground cover to create a humid microclimate for nearby plants. It keeps moisture in the ground from the top down and with its deep root system brings water and nutrients up from deeper in the soil.
As a medicinal agent:
Purslane has long been used in the treatment of urinary and digestive problems. The juice has diuretic effects. Skin conditions such as acne, psoriasis, or sunburn may benefit from purslane.
Purslane vs. Spurge:
Beware of spurge, a different-looking poisonous creeping wild plant that sometimes grows near purslane. The stem is wiry, not thick, and it gives off a white, milky sap when you break it.
Purslane as at the top of the photo and spurge is at the bottom:
Fresh from the Garden Purslane & Cucumber Salad
Sliced Cucumbers and chopped purslane tossed with garlic, olive oil, cider vinegar, salt and pepper.