Maru-moji ('rounded letters') have been a favourite among young people for many years. They are of special interest to manga and anime fans. But they're not recommended for learners unless you (1) want to annoy hell out of your teacher or (2) want to destroy any chance of ever learning to write Japanese properly.
To see the katakana equivalent of each character, pass your cursor over the top.

Table 1: The Standard Goju-on

Table 2: Syllables beginning with Voiced Consonants or 'P'

Table 4: Vowel Lengthening and Double Consonants

Katakana

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