The really quick and dirty way is to point to a local file:
<dependency>
<groupId>sample</groupId>
<artifactId>com.sample</artifactId>
<version>1.0</version>
<scope>system</scope>
<systemPath>C:\DEV\myfunnylib\yourJar.jar</systemPath>
</dependency>
However this will only live on your machine (obviously), for sharing it usually makes sense to use a proper m2 archive (nexus/artifactory) or if you do not have any of these or don't want to set one up a local maven structured archive and configure a "repository" in your pom: local:
<repositories>
<repository>
<id>my-local-repo</id>
<url>file://C:/DEV//mymvnrepo</url>
</repository>
</repositories>
remote:
<repositories>
<repository>
<id>my-remote-repo</id>
<url>http://192.168.0.1/whatever/mavenserver/youwant/repo</url>
</repository>
</repositories>
for this a relative path is also possible using the basedir variable:
<url>file:${basedir}</url>