diff --git a/plasmoidviewer/main.cpp b/plasmoidviewer/main.cpp
--- a/plasmoidviewer/main.cpp
+++ b/plasmoidviewer/main.cpp
@@ -27,19 +27,101 @@
 #include <QApplication>
 #include <QQmlDebuggingEnabler>
 
+#include <QDir>
 #include <QPixmapCache>
 #include <QDebug>
 #include <KAboutData>
 #include <KLocalizedString>
 #include <KDBusService>
 #include <KQuickAddons/QtQuickSettings>
+#include <KDesktopFile>
 
 #include <qcommandlineparser.h>
 #include <qcommandlineoption.h>
 
 #include "view.h"
 
 #include <Plasma/Theme>
+#include <Plasma/PluginLoader>
+
+#include <iostream>
+
+void listApplets()
+{
+    int maxLen = 0;
+    QMap<QString, QString> applets;
+
+    const QList<KPluginMetaData> plugins = Plasma::PluginLoader::self()->listAppletMetaData(QString());
+    for (const auto& info : plugins) {
+        if (!info.isValid() ||
+            (info.rawData().value(QStringLiteral("NoDisplay")).toBool() == true)) {
+            continue;
+        }
+
+        const QString name = info.pluginId();
+        const int len = name.length();
+        if (len > maxLen) {
+            maxLen = len;
+        }
+
+        QString comment = info.description();
+
+        if (comment.isEmpty()) {
+            comment = i18n("No description available");
+        }
+
+        applets.insert(name, comment);
+    }
+
+    for (auto it = applets.constBegin(); it != applets.constEnd(); ++it) {
+        std::cout << it.key().leftJustified(maxLen, ' ').toLocal8Bit().data() << " - "
+            << it.value().toLocal8Bit().data() << std::endl;
+    }
+}
+
+void listThemes()
+{
+    int maxLen = 0;
+    QMap<QString, QString> themes;
+
+    const QStringList basePaths = QStandardPaths::locateAll(QStandardPaths::GenericDataLocation, "plasma/desktoptheme", QStandardPaths::LocateDirectory);
+    for (const QString& basePath : basePaths) {
+        const QStringList dirNames = QDir(basePath).entryList(QDir::Dirs | QDir::Hidden);
+        for (const QString& packageName : dirNames) {
+            if (packageName == QLatin1String(".") || packageName == QLatin1String("..")) {
+                continue;
+            }
+            const QString packagePath = basePath + QLatin1Char('/') + packageName;
+            const QString metadataFile = packagePath + QLatin1String("/metadata.desktop");
+            if (!QFile::exists(metadataFile)) {
+                continue;
+            }
+
+            KDesktopFile df(metadataFile);
+
+            if (df.noDisplay()) {
+                continue;
+            }
+
+            QString name = df.readName();
+            if (name.isEmpty()) {
+                name = packageName;
+            }
+
+            const int len = packageName.length();
+            if (len > maxLen) {
+                maxLen = len;
+            }
+            themes.insert(packageName, name);
+        }
+    }
+
+    for (auto it = themes.constBegin(); it != themes.constEnd(); ++it) {
+        std::cout << it.key().leftJustified(maxLen, ' ').toLocal8Bit().data() << " - "
+            << it.value().toLocal8Bit().data() << std::endl;
+    }
+}
+
 
 int main(int argc, char **argv)
 {
@@ -86,12 +168,27 @@
                 i18n("The name of the theme which the shell will use"),
                 QStringLiteral("themeName")));
 
+    parser.addOption(QCommandLineOption(QStringList() << QStringLiteral("list"),
+                i18n("Displays a list of known applets")));
+    parser.addOption(QCommandLineOption(QStringList() << QStringLiteral("list-themes"),
+                i18n("Displays a list of known themes")));
+
     parser.addPositionalArgument(QStringLiteral("externalData"), i18n("Data that should be passed to the applet as 'externalData' event"));
 
     parser.addHelpOption();
     parser.addVersionOption();
     parser.process(app);
 
+    if (parser.isSet("list")) {
+        listApplets();
+        return 0;
+    }
+
+    if (parser.isSet("list-themes")) {
+        listThemes();
+        return 0;
+    }
+
     KDBusService service(KDBusService::Multiple);
     KQuickAddons::QtQuickSettings::init();