A few boxes drawn with Unicode box drawing characters:
╔═╦═╗
╠═╬═╣
║ ║ ║
╚═╩═╝
┏━┳━┓
┣━╋━┫
┃ ┃ ┃
┗━┻━┛
┌─┬─┐
├─┼─┤
│ │ │
└─┴─┘
╭╮
╰╯
No idea WTF this is useful for, but whatever.
╳
╱ ╲
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▏ ▕
▔▔▔
─
━
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