diff --git a/machines/machinefactory.cpp b/machines/machinefactory.cpp
index 9a2ad0e..e26ae9b 100644
--- a/machines/machinefactory.cpp
+++ b/machines/machinefactory.cpp
@@ -76,8 +76,15 @@ static const PropMap GossamerSettings = {
         new IntProperty(  2, vector<uint32_t>({2, 4, 6}))},
 };
 
-static const map<string, tuple<PropMap, function<int(void)>>> machines = {
-    {"pmg3", {GossamerSettings, create_gossamer}},
+static const map<string, string> PropHelp = {
+    {"rambank1_size",   "specifies RAM bank 1 size in MB"},
+    {"rambank2_size",   "specifies RAM bank 2 size in MB"},
+    {"rambank3_size",   "specifies RAM bank 3 size in MB"},
+    {"gfxmem_size",     "specifies video memory size in MB"},
+};
+
+static const map<string, tuple<PropMap, function<int(void)>, string>> machines = {
+    {"pmg3", {GossamerSettings, create_gossamer, "PowerMacintosh G3 (Beige)"}},
 };
 
 string machine_name_from_rom(string& rom_filepath) {
@@ -169,6 +176,30 @@ void set_machine_settings(map<string, string> &settings) {
     }
 }
 
+void list_machines() {
+    cout << endl << "Supported machines:" << endl << endl;
+
+    for (auto& mach : machines) {
+        cout << mach.first << "\t\t" << get<2>(mach.second) << endl;
+    }
+
+    cout << endl;
+}
+
+void list_properties() {
+    cout << endl;
+
+    for (auto& mach : machines) {
+        cout << get<2>(mach.second) << " properties:" << endl << endl;
+
+        for (auto& p : get<0>(mach.second)) {
+            cout << p.first << "\t\t" << PropHelp.at(p.first) << endl << endl;
+        }
+    }
+
+    cout << endl;
+}
+
 /* Read ROM file content and transfer it to the dedicated ROM region */
 void load_rom(std::ifstream& rom_file, uint32_t file_size) {
     unsigned char* sysrom_mem = new unsigned char[file_size];
diff --git a/machines/machinefactory.h b/machines/machinefactory.h
index 8c0d2a5..7cff1bf 100644
--- a/machines/machinefactory.h
+++ b/machines/machinefactory.h
@@ -38,6 +38,8 @@ std::string machine_name_from_rom(std::string& rom_filepath);
 int  get_machine_settings(string& id, map<string, string> &settings);
 void set_machine_settings(map<string, string> &settings);
 int  create_machine_for_id(string& id, string& rom_filepath);
+void list_machines(void);
+void list_properties(void);
 
 /* Machine-specific factory functions. */
 int create_gossamer(void);
diff --git a/main.cpp b/main.cpp
index c0eb436..f40c1a8 100644
--- a/main.cpp
+++ b/main.cpp
@@ -101,7 +101,14 @@ int main(int argc, char** argv) {
     CLI11_PARSE(app, argc, argv);
 
     if (*list_cmd) {
-        std::cout << "Got: " << sub_arg << std::endl;
+        if (sub_arg == "machines") {
+            list_machines();
+        } else if (sub_arg == "properties") {
+            list_properties();
+        } else {
+            cout << "Unknown list subcommand " << sub_arg << endl;
+        }
+        return 0;
     }
 
     if (debugger_enabled) {