There are are several sites like this one http://patorjk.com/software/taag/ or http://www.network-science.de/ascii/ where you can easily generate your own text logo.
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There are are several sites like this one http://patorjk.com/software/taag/ or http://www.network-science.de/ascii/ where you can easily generate your own text logo in many shapes and sizes. Here is just one: