Craiglist is a mind-blowingly useful classifieds site. Whether you are looking for friends, a job, an apartment, a hair stylist, or a ride, you will find it on the site. Registration not required.
Newegg is a popular online marketplace for computers and software. Best prices for hardware and software. Its slogan is “Once you know, you Newegg". Registration not required.
Etsy is an online marketplace to sell and buy handmade things,vintage items and so on... There are many categories, including art, photography, clothing, jewelry, books, furnitures, beauty products, toys and many more. Registration not required.
