brotherton-erpnext/erpnext/templates/includes/announcement/announcement_row.html

<div class="web-list-item blog-list-item">
	<a href="/announcements?announcement={{doc.name}}">
		<div class="row">
			<a href="/announcements?announcement={{doc.name}}">
				<div class="col-xs-12">
					<h1>{{ doc.subject }}</h1>
					<p class="post-description more">{{ doc.description }}</p>
					<p class="post-by text-muted small">
						<i>{{ doc.posted_by }}</i>
						<i class="spacer-dot"></i> {{ frappe.format_date(doc.modified) }}
						<i class="spacer-dot"></i> {{ doc.num_attachments }} attachments
					</p>
				</div>
			</a>
		</div>
	</a>
</div>

<script type="text/javascript">
	frappe.ready(function() {
		var show_char = 150;
		$('.more').each(function() {
			var content = $(this).text();
			if(content.length > show_char) {

				var c = content.substr(0, show_char)
				var h = content.substr(show_char, content.length - show_char);

				html = c + '&nbsp;&nbsp;...'
				$(this).html(html);
			}
		});
	});
</script>