A tikz solution (as standalone image):
\documentclass{standalone}
\usepackage{xcolor}
\usepackage{tikz}
\newdimen\pinA
\newdimen\pinB
\newdimen\pinC
\setlength{\pinA}{10mm}
\setlength{\pinB}{20mm}
\setlength{\pinC}{40mm}
\definecolor{pin}{gray}{0}
\begin{document}
\begin{tikzpicture}
\useasboundingbox (-\pinB, -\pinC) (\pinB, \pinB);
\pgfmathsetmacro{\pinAngle}{acos(\pinB/\pinC)}%
\pgfmathsetmacro{\pinAngleRight}{270+\pinAngle}%
\path[fill=pin, even odd rule]
(\pinAngleRight:\pinB)
arc[
at={(0,0)},
start angle=\pinAngleRight,
delta angle=360-2*\pinAngle,
radius=\pinB,
]
-- (0, -\pinC) -- cycle
circle[
at={(0,0)},
radius=\pinA,
]
;
\end{tikzpicture}
\end{document}

The both radii and the length of the tip can be configured using the dimen registers \pinA, \pinB, \pinC, all three measured from the origin in the middle of the circles. The color can be set via color name pin.
Usage
The file can be stored as pin.tex, then run pdflatex pin to get pin.pdf.
The following example automatically scales the image to the size of uppercase letters, when included as image:
\documentclass{article}
\usepackage{graphicx}
\usepackage{calc}
\newcommand*{\pin}{%
\includegraphics[height=\heightof{M}]{pin}%
}
\begin{document}
{\Huge \pin~Hello World}
{\normalsize \pin~Hello World}
{\tiny \pin~Hello World}
\end{document}
