A custom filter allows you to create a linked item using a join

Save the following in a file such as appname/templatetags/custom_tags.py

from django import template
register = template.Library()

@register.filter('join_link')
def join_link(value, arg):
    from django.utils.html import conditional_escape
    arr = []
    for i in value:
        arr.append('<a href="%s">%s</a>' % (
            i.get_absolute_url(), conditional_escape(i)
        ))

    return arg.join(arr)

In your template add the following, assuming posts is a Queryset from Post.objects.all() or something.

{% load custom_tags %}

{{ posts|join_link:', '|safe }}

This would produce something like (line-break for formatting on here only)

<a href="/news/hello-world.html">Hello World</a>,
<a href="/news/goodbye-world.html">Goodbye world</a>

This example does use get_absolute_url as well as automatically using the __str__ or __unicode__ methods, so these will need to be defined in your model.

More on creating custom filters