LaTeX "under construction", "in work" or "work in progress" symbols
Well it's not rocket science either
\begin{tikzpicture}[limb/.style={line cap=round,line width=1.5mm,line join=bevel}]
\draw[line width=2mm,rounded corners,fill=yellow] (-2,0) -- (0,-2) -- (2,0) -- (0,2) -- cycle;
\fill (1.5mm,7mm) circle (1.5mm);
\fill(0,-7.5mm) -- ++(10mm,0mm) -- ++(120:2mm)--++(100:1mm)--++(150:2mm) arc (70:170:2.5mm and 1mm);
\draw[limb] (-7.5mm,-6.5mm)--++(70:4mm)--++(85:4mm) coordinate(a)--++(-45:5mm)--(-2.5mm,-6.5mm);
\fill[rotate around={45:(a)}] ([shift={(-0.5mm,0.55mm)}]a) --++(0mm,-3mm)--++
(7mm,-0.5mm)coordinate(b)--++(0mm,4mm)coordinate(c)--cycle;
\draw[limb] ([shift={(-0.6mm,-0.4mm)}]b) --++(-120:5mm) ([shift={(-0.5mm,-0.5mm)}]c) --++
(-3mm,0mm)--++(-100:3mm)coordinate (d);
\draw[ultra thick] (d) -- ++(-45:1.25cm);
\end{tikzpicture}
I didn't find such a sign in the LaTeX symbol guide, so here is a tikz solution: Look for a nice sign on Wikipedia, download the svg file, convert svg to tikz with Inkscape. Then you can build a command like this:
\documentclass{article}
\usepackage{pifont}
\usepackage{tikz}
\definecolor{cec1d24}{RGB}{236,29,36}
\definecolor{cffffff}{RGB}{255,255,255}
\newcommand{\cmark}{\ding{51}}
\newcommand{\ucmark}{\tikz[y=0.80pt,x=0.80pt,yscale=-0.02,xscale=0.02, inner sep=0pt, outer sep=0pt]%
{\path[fill=cec1d24,nonzero rule] (635.8833,600.0000) .. controls
(651.0771,599.6647) and (665.7558,591.6224) .. (673.9783,577.5525) .. controls
(682.1001,563.3625) and (681.7384,546.6500) .. (674.5074,533.1862) --
(378.4699,21.6487) .. controls (370.6590,8.7662) and (356.3424,0.0975) ..
(340.1099,-0.0063) .. controls (323.6499,0.0972) and (309.3362,8.7657) ..
(301.4862,21.6487) -- (5.4612,533.1862) .. controls (-1.7257,546.6500) and
(-2.0877,563.3625) .. (5.9903,577.5525) .. controls (14.2570,591.6225) and
(28.9353,599.6650) .. (44.0853,600.0000) -- (635.8853,600.0000);
\path[fill=cffffff,nonzero rule] (340.1208,75.7875) -- (71.0683,540.8450) --
(608.8933,540.8450) -- (340.1058,75.7950);
\path[fill=black,nonzero rule] (303.5900,225.7800) .. controls
(280.4500,225.7300) and (276.9200,248.1400) .. (276.8800,250.6200) .. controls
(276.9200,262.4400) and (285.4000,277.1700) .. (309.1600,279.4100) .. controls
(309.1600,279.4100) and (313.7700,280.0900) .. (313.6600,283.0900) .. controls
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cycle(394.8800,275.9700) .. controls (394.8800,275.9700) and
(408.4700,275.8400) .. (411.5300,276.2200) .. controls (414.3400,276.5000) and
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(331.0000,332.8100) -- cycle;}}
\pagenumbering{gobble}
\begin{document}
\section*{Tasks}
\begin{enumerate}
\item Design \cmark
\item Implementation \ucmark
\end{enumerate}
\end{document}
The output is:
If you're open to using XeTeX or LuaTeX, you might find some possibilities in the excellent fontawesome font and its corresponding package (containing easy-to-use macros). Here are a few options:
\documentclass{article}
\usepackage{fontawesome} % requires XeTeX or LuaTeX
\newcommand{\cmark}{\faOk}
\newcommand{\pmark}{\faWarningSign}
\begin{document}
\section*{Tasks}
\begin{enumerate}
\item Design \cmark
\item Implementation \pmark
\item Another option \faWrench
\end{enumerate}
\end{document}
