The Swiss canton of Glarus still practices the concept of the Landsgemeinde. Quoting from Wikipedia:
Eligible citizens of the canton meet on a certain day in the open air to decide on laws and expenditures by the council. Everyone can debate a question. Voting is accomplished by those in favour of a motion raising their hands.
In Switzerland, this is practiced by the cantons of Glarus and Appenzell-Innerrhoden. The German-language Wikipedia article Gemeindeversammlung tells us that most Swiss municipalities use a similar system, but that details differ locally. The linked English-language article on town meeting describes a number of examples in the United States, although the article on open town meeting seems more similar to what the German language article describes and what is practiced in Switzerland. The examples described here are mostly in New England.
What are the main arguments in favour and against decision-taking by general assemblies, compared to other forms of direct democracy?