Answer by Heiko Oberdiek for Small cross and small upside down cross symbols

A solution that uses simple rules:

\documentclass{article}\usepackage{amsmath}\newcommand*{\crosssymbol}{%% \mathbin{%    \text{%      \raise 1ex\hbox{%        \rlap{\vrule height.2pt depth.2pt width .75ex}%        \hbox to .75ex{\hss\vrule height .5ex depth 1ex\hss}%      }%    }%  % }%}\newcommand*{\crossupsidedown}{%% \mathbin{%    \text{%      \raise .5ex\hbox{%        \rlap{\vrule height.2pt depth.2pt width .75ex}%        \hbox to .75ex{\hss\vrule height 1ex depth .5ex\hss}%      }%    }%  % }%}\begin{document}$\dag\,\crosssymbol\crossupsidedown\,\mathsf{t}$\end{document}

The same file translated into "pure LaTeX":

\documentclass{article}\usepackage{amsmath}\newcommand*{\crosssymbol}{%% \mathbin{%    \text{%      \raisebox{1ex}{%        \makebox[0pt][l]{%          \rule[-.2pt]{.75ex}{.4pt}%        }%          \makebox[.75ex]{%          \rule[-1ex]{.4pt}{1.5ex}%        }%      }%    }%  % }%    }   \newcommand*{\crossupsidedown}{%% \mathbin{%    \text{%      \raisebox{.5ex}{%        \makebox[0pt][l]{%          \rule[-.2pt]{.75ex}{.4pt}%        }%        \makebox[.75ex]{%          \rule[-.5ex]{.4pt}{1.5ex}%        }%      }%    }%% }%}\begin{document}\(\dag\,\crosssymbol\crossupsidedown\,\mathsf{t}\)\end{document}

Remarks:

• I do not know the purpose of the symbols, therefore you might want to add \mathbin or \mathrel to get the horizontal spacing right.